Preheat the oven to 400°F (200°C).
Combine the chili powder, garlic powder, ground cumin, paprika (if using), salt, and black pepper in a small bowl to make the dry spice mix.
Lay each chicken breast half flat on a cutting board and sprinkle both sides evenly with the dry spice mix.
Place 6 bell pepper slices (about 2 of each color) across the center of each seasoned chicken cutlet.
Tightly roll each cutlet around the peppers, place seam-side down, and secure with toothpicks; sprinkle any remaining spice mix over the rolls.
Heat the olive oil in a large heavy skillet over medium-high heat until shimmering.
Add the chicken roll-ups and sear for 2–3 minutes per side, until golden brown on all sides.
If using an oven-safe skillet, transfer the skillet to the preheated oven; otherwise move the rolls to a baking sheet.
Bake for about 15 minutes, or until the chicken is fully cooked through and the peppers are slightly charred.
Remove toothpicks, garnish with chopped cilantro and a squeeze of lime if desired, and serve with vegetables, rice, or tortillas.