Preheat the oven to 350 degrees Fahrenheit.

Heat olive oil in a small skillet over low heat.

Add the minced onion to the skillet and sauté until lightly browned.

In a large mixing bowl, combine the sautéed onion, cooked brown rice, grated cheddar cheese, ricotta cheese, chopped jalapeno pepper (or minced green chilies), chopped cilantro, ground cumin, salt, and pepper.

Stir all ingredients together until thoroughly combined.

Lightly oil a 1 1/2-quart baking casserole dish.

Pour the rice mixture into the prepared casserole dish.

Bake in the preheated oven for 35 minutes, or until the top is golden brown and bubbly.

Let cool slightly before serving.