Heat oven to 400 degrees. Spray 10 inch pie plate with Pam. Cook ground chuck until done, pour taco seasoning mix over meat and stir all together. Spread in pie plate. In a blender pour in the milk, eggs and bisquick and blend until smooth. Pour evenly over the meat. Do not stir. Bake for 25 minutes. Sprinkle cheese on top and bake another 5-10 minutes until cheese melts. Top with diced tomatoes, lettuce, and sour cream.