Heat the oil in a large skillet over medium heat until smoking.
Add onion and saute for about 5 minutes until it begins to brown.
Add diced jalapeno just as the onion starts to brown
Add the beef and break it into 4 or 5 large chunks. Cook for 5 minutes undisturbed.
Break the beef into small crumbles and cook until browned on the outside.
Make a hot spot in the pan by clearing the meat and add a very small amount of oil in this spot, about half a teaspoon.
Now add the garlic to the hot spot and let it cook for about 1 minute before mixing it into the rest of the ingredients.
Season with chili poweder, cumin, salt, and pepper. Stir so that everything is well mixed.
Add a small amount of water to the pan (about a teaspoon), lower the temperature to medium-low, cover and continue to cook until the meat is no longer pink on the inside (approximately 5-7 more minutes).