01 - Preheat your grill to medium heat, approximately 350°F to 400°F.
02 - In a skillet over medium heat, add butter or olive oil. Sauté the onion until translucent, about 3 minutes.
03 - Stir in sauerkraut, caraway seeds (if using), black pepper, and sugar. Cook, stirring occasionally, for 5–7 minutes until warmed through and flavors meld. Keep warm.
04 - Place halal bratwurst on the grill. Cook, turning occasionally, for 10–12 minutes until evenly browned and heated through to an internal temperature of 160°F.
05 - Toast the buns lightly on the grill for 1–2 minutes until golden and slightly crisp.
06 - Place a grilled bratwurst in each bun. Top generously with warm sauerkraut mixture.
07 - Drizzle with mustard and add parsley, jalapeños, or pickles as desired. Serve immediately while hot.