In a LARGE skillet with a small amount of oil, saute onion for 2-3 minutes.  Add ground meat and cook until it is no longer pink, draining if needed.  Add all additional ingredients (except the tortillas) to the skillet.  You may find that you need to add slightly more water to create a mixture that is to your liking.  You just don't want it to be runny.  (If you like a spicier burrito, use hot salsa, more cayenne and the full amount of black pepper.)  Heat mixture until heated through and prepare to wrap your burritos.  Scoop 1/3-1/2 cup of filling onto each tortilla; I use a large cookie scoop with a thumb lever for this step.  Roll burrito from beginning end, folding in sides as your roll toward the ending edge of the tortilla.  This step fully encloses the filling in the tortilla. 

At this point, I wrap the burritos we won't be eating for dinner in sheets of foil, then bag them and freeze them until we're ready to eat them again.  One burrito removed of it's foil, takes 5 minutes on defrost and 1 minute of cook time in my microwave.  Obviously more burritos = more time in the microwave.  ;)

If I'm thawing them for a family meal and want to bake them instead of microwaving, I would place them in a single layer, to thaw in the refrigerator, the night before I intend to use them.  Bake in their foil until hot; maybe 45 minutes at 350 degrees.  ...But the microwave works so well that we don't usually bother with the oven for reheating. 

These are a HUGE family hit, so I hope that you enjoy them too!  Let me know what you think if you make them.   ....Or if I've forgotten an ingredient, amount or instruction.  ;)