Chop garlic, onion, and mushrooms finely. Sauté garlic and onion in a pan with oil, then add mushrooms and sprinkle with salt. Cook until vegetables soften.

In a pan over low heat, melt butter and gradually add flour while stirring continuously. Once thickened, slowly add milk while stirring to create a smooth béchamel sauce.

Steam or microwave the pumpkin until soft. Remove seeds and tough skin, then mash the pumpkin into small pieces.

Combine the sautéed vegetables, mashed pumpkin, and béchamel sauce in a bowl and mix well.

Transfer the mixture into an oven-safe dish and cover with mozzarella cheese.

Bake in a preheated oven at 200°C for 8-10 minutes until the cheese melts and turns golden.