Brown the ground beef in a large skillet over medium heat, breaking it apart as it cooks until there's no pink left.
Drain off the extra fat so your sauce doesn't end up greasy.
Finely mince the red and green bell peppers; either by hand or with a few pulses in a food processor.
You want them small, not mushy.
Stir the peppers into the drained beef and lower the heat.
Whisk tomato paste, water, corn syrup, vinegar, cornstarch, dried onion, chili powder, salt, Worcestershire, allspice, cloves, garlic powder, and red pepper flakes in a bowl until smooth.
Make sure the cornstarch dissolves completely; nobody likes lumps.
Pour this sauce mixture into a saucepan, toss in the bay leaf, and bring it to a gentle boil while whisking for about a minute.
Let it cook for 5 minutes over medium heat, just until it thickens a bit.
Fish out the bay leaf, then stir the thickened sauce into your skillet with beef and peppers.
Simmer on low for 5 to 10 minutes, stirring now and then, until it thickens up and coats the meat nicely.