Heat olive oil in a large skillet over medium heat. Add butter and when it melts, add onion, coriander, and bay leaf to skillet. Cook for about 3 minutes to soften onion.
Add tomatoes to skillet and cook for 3 more minutes before adding the squash, sage, garlic powder, salt, and pepper.
Turn down the heat, cover the pan, and let cook for about 30 minutes until the squash softens.
When squash is softened, remove bay leaf from skillet and stir in parsley and parmesan.
Pre-heat oven to 350 degrees.
Lightly butter a 10-inch casserole dish and add squash mixture to dish. Spoon the crumb topping over the veggies.
Bake squash crumble for 30-35 minutes, until golden on top.