Slice the kielbasa into ¼-inch thick rounds or half-moons—this shape maximizes the surface area for browning and makes eating easier. Mince your garlic, dice the onion into bite-sized pieces, and cut the cabbage into 1-inch thick ribbons by halving it lengthwise, removing the core, then slicing crosswise. Having everything prepped before you start cooking ensures you can move quickly through the next steps without scrambling.

Heat the olive oil in a large skillet over medium-high heat until shimmering. Add the sausage slices in a single layer and let them cook undisturbed for 2-3 minutes until the bottoms develop a golden-brown crust. Flip and cook the other side for another 2-3 minutes. Transfer the browned sausage to a clean plate and set aside—don't worry about cooking it completely through; it will finish cooking when it returns to the pan.

Reduce the heat to medium-low and add the diced onion to the same skillet with the rendered fat. Cook for 4-5 minutes, stirring occasionally, until the onion becomes soft and translucent. This gentle cooking allows the onion to release its natural sweetness without browning, creating a flavorful base for the cabbage.

Add the minced garlic to the softened onions and cook for 30 seconds until fragrant, then add the cabbage ribbons, salt, pepper, and smoked paprika. The paprika adds a subtle smoky depth that complements the sausage beautifully. Stir everything together to coat the cabbage with the oil and aromatics, then cover the skillet and cook for 10-12 minutes, stirring every 4-5 minutes. I like to lift the lid periodically and smell the cabbage—when it smells sweet and tender rather than raw, you're close to done.

Return the browned sausage to the skillet along with the red wine vinegar. Stir well to distribute everything evenly, then cover and cook for 2-3 minutes more until the sausage is heated through and the flavors meld. The vinegar adds a bright, acidic punch that cuts through the richness of the fat and sausage, balancing the dish beautifully.