Slice the sausage into ½-inch coins (or leave the links whole — whole-link times are in the method H2s) and pat dry with paper towels.
Heat the olive oil in a large cast-iron skillet over medium heat.
Add the coins in a single layer — don't overcrowd — and sear 3–4 minutes per side until deeply browned on the cut faces and heated through (whole links: 2–3 minutes per side).
Push the sausage to the edges, add the onion and bell pepper with the smoked paprika, garlic powder and black pepper, and cook 5–6 minutes until soft and lightly caramelised.
Rest 2–3 minutes before serving. Serve on toasted buns with Dijon and sauerkraut, or over rice.