If you’re making homemade pizza dough, prepare it in advance.
Preheat oven to 385°.
Slice your acorn squash into thin strips and arrange on a baking sheet. Brush the sliced acorn squash with olive oil. If you’re using peppers, add them to the baking sheet as well. Roast the squash and peppers for 25 minutes, flipping halfway through.
While your squash and peppers are roasting, caramelize your onion. Add half of your olive oil to the pan and sauté your sliced onions for about 20 minutes on low heat. They should be translucent and soft when done. Add the minced garlic to the onion and sauté for 2 minutes more. Remove from heat and set aside.
In the same pan, brown your sausage. Once the sausage is finished, combine it with the onion and garlic mixture.
Remove squash from the oven and peel skins off slices. Finely slice your peppers Increase oven temperature to 425.
Place your prepared pizza dough on a parchment-lined pan or a baking stone and brush lightly with olive oil.
Layer the sausage, onion, and garlic mixture on the dough, and add the sliced squash and pepper to the pizza. Sprinkle with Parmesan cheese and bake for 20 minutes, or until edges of the pizza are very slightly browned.
While your pizza is cooking, toast your pumpkin seeds. Place seeds in a small pan and stir over low heat for 3-5 minutes, until the seeds begin to smell fragrant. Remove from heat and set aside.
Once the pizza has finished baking, top it with arugula, coat cheese crumbles and the toasted pumpkin seeds.
If desired, drizzle pizza slices with Sriracha and/or additional olive oil.