Heat olive oil in a large skillet or Dutch oven over medium-high heat. When the oil shimmers, add the ground beef, onion, and bell pepper. Break up the meat with a wooden spoon, and cook until the meat is no longer pink, about 7 minutes. Add the garlic and cook for 1 more minute. Drain off the excess fat.
Add the remaining ingredients to the skillet, as well as about ¾ teaspoon of salt and a dash of pepper.
Stir to combine; bring to a boil. Once the mixture boils, reduce the heat to a simmer. Cook, uncovered, for about 12-15 minutes, or until the noodles are tender and the sauce thickens.
Taste and season with additional salt and pepper, if necessary. Garnish with cheese and parsley, if desired.
