Pre-heat oven to 450 degrees.
Toss cubed butternut squash with 1 Tbsp olive oil and season with salt and pepper. Place in a single layer on a baking sheet and roast for about 20-30 minutes, until tender and nicely browned. Toss squash after about 10 minutes of cooking time.
While squash is roasting, heat remaining 1 Tbsp olive oil in a large skillet and add 1 Tbsp butter. Add sliced onion and cook on low until caramelized, about 25-30 minutes. Add garlic, sauté for a few more minutes and set aside.
Transfer caramelized onions to a plate and melt remaining 1 Tbsp butter in skillet. Let the butter brown a bit and then add the sage leaves. Sauté for about 2-3 minutes, until crispy.
Add onions, squash, and gorgonzola to the pan and toss (try not to let the cheese melt). Serve!