In a bowl, combine pumpkin puree, ricotta, Parmesan cheese, salt, onion powder, nutmeg, and pepper. Mix well and set aside.
Lightly flour a ravioli maker and place a pasta sheet over it, gently pressing to create pockets. Add about 1 tablespoon of pumpkin filling into each pocket, brush the edges with water, and cover with another pasta sheet.
Use a rolling pin to seal and cut the ravioli. Remove the ravioli from the mold and place them on a parchment-lined baking sheet. Repeat with remaining pasta sheets and filling.
For the sauce, melt butter in a large skillet over medium heat until foamy. Reduce heat and cook until the butter turns golden brown and develops a nutty aroma, about 4 minutes.
Add garlic, sage leaves, and pumpkin spice pecans. Cook for 1–2 minutes until fragrant and the sage becomes crisp. Remove from heat.
Bring a large pot of salted water to a boil. Cook ravioli in batches for 2–3 minutes, or until they float. Transfer cooked ravioli directly into the brown butter sauce using a slotted spoon.
Return the skillet to medium-low heat and gently toss the ravioli in the sauce until evenly coated.
Serve warm topped with extra pecans, Parmesan cheese, and a pinch of salt.