Fill a large pot with water and set it over high heat to boil.

When the water reaches a full boil, add 1 tablespoon kosher salt.

Add the bow tie pasta to the pot and stir well so the pieces do not stick together.

Cook the pasta until it is tender but still a little firm in the center, using the package time as a guide, usually 10 to 12 minutes.

While the pasta cooks, set a large skillet over medium-high heat.

Put the sliced kielbasa into the dry skillet in one layer and cook without stirring for 3 to 4 minutes, until the first side is browned.

Stir the kielbasa and cook for 2 to 3 minutes more, until browned in spots. Transfer the kielbasa to a plate and leave the rendered fat in the skillet.

Turn the heat under the skillet down to medium. Add the sliced onion and cook for 2 to 3 minutes, stirring often, until it starts to soften. If the skillet looks dry, splash in 2 tablespoons of water from the pasta pot.

Add the sliced cabbage to the skillet along with 1/2 teaspoon of the black pepper.

Cook the cabbage for 5 to 6 minutes, stirring every minute, until it has wilted down and looks glossy with a few browned edges.

In a small bowl, stir the sour cream and Dijon mustard together until smooth.

When the pasta is ready, scoop 1 cup of the pasta cooking water into a measuring cup or mug.