Taco Rice

1 lb hamburger
1 medium onion, chopped
1/2 pkg of taco seasoning
1-16 oz chunk tomatoes
1 C rice, uncooked
1 C mayonnaise
1 C sour cream
1 C shredded cheese
2 C Bisquick mix
3 /4 C milk

Fry hamburger until browned, adding onions last minute of browning.  Add taco seasoning and drained tomatoes.  Drain juice from tomatoes, add enough water to make 2 1/2 cups liquid.  Cook the rice in the tomato juice and water mixture.  When the rice is soft, mix with hamburger mixture.  Pour into 9 X 13-inch pan.  Mix together mayonnaise, sour cream, and cheese, and spread over hamburger mixture.  Make a batter of Bisquick and milk and pour over top of sour cream mixture.  Bake at 400 degrees for 30 minutes.