I'll admit it. For years, the only way I ever prepared butternut squash was to roast them whole and then scoop out the flesh from the finally softened peelings. Sometimes I would be so brave as to cut them in half, take out the seeds, and turn them upside down on a baking sheet to speed up the roasting a bit, but every push of the knife into those wobbly pear-shaped things raised my anxiety level to a fever pitch.
You do need to understand my history around sharp objects is not a really good one, and I have a string of anecdotes about kitchen mis-steps and subsequent stitches, so my fear was not entirely groundless. Still, as a result of my conservative approach, I was missing out on some really good recipes. Finally, when I came into a stash--an entire bushels-worth!--of deep yellow butternut squash one fall, I knew I needed to try some of the great recipes I had seen that called for diced or even shredded squash.
Now, several years later, my fingers all firmly intact and not even slightly gashed, I have some suggestions that might help you if you also fear these hard-shelled garden treasures.
(Scroll all the way to the end for a hint of how your microwave might be of help with this whole process. There are also some links there that include a few recipes to try with your cubed squash.)
To start, you need the right equipment. A large cutting board is important, preferably wood, as it is less likely to slide around than the thin plastic sheets, and a glass cutting board is too hard on your knives.
Next, you need to select the right knives. Contrary to what many cooking shows would have us believe, you don't always need great big knives. In fact, too large a knife for some tasks can be downright dangerous. On the other hand, you should have a large, relatively heavy bladed knife for doing the initial "hacking" up of your squash.
As you can see in these pictures, I use two different knives for getting my squash cut into cubes. The larger one has a serrated blade (reluctant admission: it is a "ginzu knife" I bought at a supermarket demonstration, one of the best bargains I have made in my cooking career). I like the serration because it seems to grip the flesh of the squash with less likelihood of slipping off the side of the squash. If you have a large "chef's knife" or even a heavy, serrated, bread knife, these can work well too.
Another advantage to serrated (or "granton edge," wavy bladed) knives is that they tend to keep their sharpness. It is not an old wives tale that dull knives can be more dangerous than sharp ones. When cutting into a squash, you want to start gently and push slowly, without too much pressure, so that the blade doesn't suddenly slip off the squash--and likely right on to the hand you are using to steady the thing!
For whatever reason, most of us seem to think of cutting squashes like these in half from top to bottom, and that is the way I first learned to cut them. However, a far easier, and safer, way to cut is to begin at the top of the squash and cut slices, as though you are cutting bread. Saw gently into the squash about an inch or so from the top and then continue slicing until you reach the seed "bowl" at the bottom.
When you reach this bottom part, you can either leave it as a "bowl," scooping out the seeds and baking it with a stuffing, much like you would stuff an acorn squash. However, if you just want to use this part of the squash along with the rest, cut the bowl in half (or if very large, in quarters) and scoop out the seeds. An ordinary tablespoon or a grapefruit spoon can be the best tool for this.
Now that you have the slices cut, you could just put them into a roasting pan coated with some oil, cover them with foil, and roast at anywhere from 375 to 450 (your choice) until they are soft, with the flesh easily pierced with a fork. Remove from the oven and, as soon as cool enough to handle, slip the peelings off easily with a small knife.
If, however, you want to cube the squash for use in sautes, an Indian curry, etc., you now need to peel them. Remember when I mentioned having the right tools? Now is the time for a small, but still very sharp, knife, definitely nothing too big. You need a good paring knife--paring as in paring, removing the peel from something, right? Good.
Now here is the next step that I almost hesitate to share. The easiest way to peel these pretty rounds of squash is not to use a cutting board. Instead, you are going to use a time-honored and potentially dangerous method. You are going to take the round of squash in one hand and then gently take the small but sharp knife in the other hand and begin cutting the peeling off the squash slice, pulling the blade toward yourself.
Some key words: A sharp knife and a gentle cut. You don't want to push too hard with the knife or try to cut too fast. However, once you have tried this a few times, you will see that it is really not very difficult at all. In fact, it is much, much easier than slashing downward on the squash while it sits on a cutting board.
Once you have the slices peeled, you can now cut them into cubes. Maybe the better word is chunks, since the irregular shape of the squash is going to mean that the pieces are going to be only roughly the shape of a mathematically perfect cube, and that is perfectly okay. The key is to keep them uniform enough that they will be finished cooking at about the same time.
To cut the slices quickly, cut a slice (or oval from the bowl-shaped section) into long strips and then line the strips up next to each other on your cutting board. Use your large knife to cut through several of these strips at a time. Do NOT try to stack the slices on top of each other, as they are slippery and too easily slide off such a stack and, again, possibly right on to the fingers you are using to steady the slices. (Not that I have any experience with such an event of course!)
In no time at all, you will have a large supply of cubed squash ready for all kinds of cooking adventures. Even a medium squash will provide enough cubes for several recipes. Packed into a plastic bag, the uncooked cubes will keep in the refrigerator for a few days, so you can try out a couple of different dishes with your stash.
I don't recommend freezing the raw squash cubes. If you discover that your squash is going to yield way too many cubes to use right away, you might want to peel and cube just enough for what you need and roast the rest of the squash slices as noted above. Once the squash is roasted, it can be mashed or pureed and then frozen for recipes that call for this form.
A few recipes you can try using your cubed squash:
Barley with Butternut Squash and Apples
My Daughter's Great Tree Hugger Chili
You Have to Try It to Believe It Soup
Now, the Microwave Hint
If you still find it very difficult to peel your recalcitrant squash, you may want to try this approach. Wash the squash and pierce it in several places, especially around the seed cavity section. Place the squash in the microwave and heat it on full power for one to three minutes, depending on the size of the squash. You are not trying to cook it, just getting it ever so slightly softer so it will be easier to cut. Take the squash out of the microwave and allow to cool just long enough to be comfortable handling it. Now, it should be just a little less hard as you proceed with the steps above.