Heat oven to 350 F. In large skillet, heat canola oil. Cook peppers, onion and cumin until tender.
In saucepan, add water and brown rice. Cook 45 minutes.
In saucepan, add 1 1/4 cups evaporated milk, shredded cheese and green chilies. Cook over medium heat until cheese is melted and smooth.
Stir 3/4 cheese mixture in with rice; set remaining cheese sauce aside.
In medium bowl, add refried beans and remaining evaporated milk. Microwave 3-4 minutes.
Lay out tortillas and layer: refried bean mixture, rice mixture and pepper-onion mixture. Roll into burritos and place in baking pan. Top burritos with remaining cheese sauce. Bake 20-25 minutes.
Garnish with salsa and guacamole, if desired.