01 - In a mixing bowl, blend all-purpose flour and salt. Pour in water and olive oil. Stir to combine, then knead on a clean surface for 5 to 7 minutes until a smooth, elastic dough forms. Cover and set aside for 20 minutes.
02 - In a separate bowl, stir together pumpkin purée, chopped walnuts, nutritional yeast, ground nutmeg, garlic powder, black pepper, salt, and olive oil. Mix until the filling reaches a creamy consistency.
03 - Divide dough into two equal portions. Dust a countertop with flour and roll each half into a thin, even sheet approximately 1/16 inch thick.
04 - On one sheet of dough, distribute teaspoon-sized mounds of filling 1 inch apart. Moisten dough edges with water. Cover with the second dough sheet, pressing gently around each mound to seal, then cut into squares using a ravioli cutter or sharp knife.
05 - Bring a large pot of salted water to a gentle boil. Add ravioli in batches and simmer for 3 to 4 minutes, or until they float to the surface. Transfer to a plate with a slotted spoon.
06 - In a skillet, melt vegan butter over medium heat. Add sage leaves and sauté for 2 to 3 minutes until fragrant and crisp.
07 - Gently toss cooked ravioli with sage butter sauce in the skillet. Adjust seasoning with salt and black pepper before serving.