Put the ground chuck in a large pot or Dutch oven and add seasonings.
Add just enough water to cover the meat, bring to a boil, then reduce and simmer for about an hour.
Every 15 minutes or so break up the meat with a large spoon or a potato masher so that it isn't lumpy. Be sure always to keep just enough water to cover the meat.
After an hour add the onion and bell pepper and simmer another 20 minutes. The meat should be very finely textured at this point.
Remove from the heat, pour into a strainer over a large bowl, and let the meat sit in the strainer for 10 or 15 minutes to make sure all grease drains away, pressing it a few times.
After the meat has drained as much as possible, place the bowl of liquid (which you want to keep) and grease in the freezer for a while. When grease separates and hardens on top, take a spoon and remove all of it. Retain about a cup of the degreased liquid.
Place reserved liquid in a pan and bring to a boil. Dissolve 1 teaspoon of corn starch in 1/4 cup of cold water and add to the liquid, simmering 4 or 5 more minutes. Add reserved meat into the pan and mix liquid well into meat.
Serve in taco shells or tortillas, or mix into a taco salad or casserole.