Mushroom and spinach sauce

This was a perfect fiber-rich vegetarian topper for brown rice. Quick and easy to prepare, and rather cheap, considering I got all the veggies discounted.

Ingredients
16 oz portobella mushrooms
16 oz baby spinach
1/3 cup heavy cream
2 cloves garlic
0.5 tsp pepper flakes
1 yellow onion
2 oz grated Parmesan
0.25 tsp ground nutmeg
1 tbsp butter
salt
black pepper

Preparation
Brown the sliced mushrooms in the butter. Remove the mushrooms and caramelize the onions in the same pan. Add the crushed garlic and pepper flakes. Add in the spinach and wilt.

Add back the mushrooms, sprinkle with ground nutmeg. Pour in the heavy cream. Simmer for a few minutes.

Stir in the grated Parmesan and simmer for another minute. Serve over freshly cooked brown rice.