Heat a nonstick skillet or Dutch oven over medium-high heat and add ground beef. Cook, breaking apart with a wooden spoon, until about halfway cooked. Add onion and red bell pepper and continue to cook until vegetables are softened. If there is excess grease, you can remove it with a spoon before proceeding.: The pan should sizzle when the ground beef hits the surface, releasing a meaty aroma and a faint pop as fat renders. As the meat browns, you'll notice little browned bits, these are flavor gold, so keep the heat even to avoid burning. When the mixture is halfway cooked, the onion will begin to turn translucent and emit a sweet fragrance, while the red bell pepper will soften and slightly caramelize, adding color and a gentle sweetness. Use a wooden spoon to break the meat into coarse crumbles, ensuring even browning. If the pan accumulates excess grease, carefully spoon it away to prevent a greasy sauce, but leave enough fond for flavor. A common mistake is overcrowding the pan, which causes steaming rather than browning; if your pan is too small, work in batches or use a larger Dutch oven.
Add chili powder, cumin, salt, oregano, and garlic powder and cook for 30 seconds while stirring.: Right after the vegetables soften, add the spices and salt so the heat will bloom their oils, which unlocks aroma and deeper taste. You should hear a soft sizzle and smell a warm, toasty fragrance as the spices toast briefly. Stir constantly for about half a minute so the heat does not scorch the powders; toasting too long will turn the spices bitter. This quick step builds the spice backbone and helps the flavors integrate into the meat and vegetables. Avoid adding the spices too early in cold pans, as they may clump and fail to distribute evenly.
Add chicken broth, Dr. Pepper, diced tomatoes, tomato paste, chipotle chilis, and Worcestershire sauce. Stir to mix well. Simmer for 20 to 30 minutes or until chili has thickened to your liking. Add kidney beans.: When you add the liquids and concentrated tomato, the pot will go from dry to active, releasing steam and a complex perfume of sweet, smoky, and savory notes. The Dr Pepper will begin to reduce and concentrate, lending a glossy sheen to the sauce, while the fire roasted tomatoes and tomato paste increase body and acidity. As it simmers, you should hear a gentle bubbling and see the sauce thicken as moisture evaporates. Stir occasionally to prevent sticking and to taste for seasoning as flavors meld. Adding the chopped chipotle peppers in adobo sauce at this stage enables their smokiness to infuse the whole pot evenly; if you want less heat, add fewer. Simmering too vigorously can cause reduction to be too fast and concentrate salt and spice, so keep the heat at a steady low simmer. After the sauce reaches your desired thickness, fold in the drained kidney beans so they warm through and pick up the sauce flavors without breaking apart.
Serve with sour cream, red onion, and cilantro.: As you ladle the chili into bowls, the aroma should be a complex mix of smoky chipotle , sweet reduction from the Dr Pepper , and savory tomato and beef notes. A dollop of sour cream will introduce cool creaminess, calming heat and adding silkiness. Finely sliced red onion provides a crisp, slightly sharp bite that contrasts the rich stew, while chopped cilantro adds a fresh, herbal finish. Arrange garnishes individually so guests can customize. A common oversight is adding garnishes too early into the pot; reserve them for plating to maintain texture and color contrast.