Caramelized Cabbage & Walnut Pasta

​¼cup olive oil
3tablespoon unsalted butter
2teaspoon cumin seeds
2leeks, white and tender green parts, thinly sliced into rings
4garlic cloves, finely chopped
2pounds finely sliced green cabbage
Kosher salt (Diamond Crystal)
1pound spaghetti or other long pasta
4ounces pecorino, grated, plus more for serving
2 to 3teaspoons freshly ground black pepper, plus more as needed
3 to 4tablespoons lemon juice (from 1 large lemon)
1to 1½ cups toasted walnuts, roughly chopped
Handful of chopped chives (optional)

Bacon (optional)

​Heat a large Dutch oven or pot over medium. Add the olive oil and butter. When the butter has melted, add cumin seeds and bloom for 15 seconds, then add the leeks, garlic, cabbage and 2 teaspoons salt, and stir for 3 to 4 minutes until wilted. Cover, reduce heat to medium-low and cook for 10 minutes without stirring. Check every few minutes to make sure the bottom is not burning. If needed, give it a stir. After 10 minutes, remove the lid from the cabbage and stir. Cover and cook for another 4 to 5 minutes, until it is supersweet and tender. Taste and season with kosher salt. Meanwhile, bring a large pot of salted water to a boil. Add the spaghetti and cook according to package instructions. When the pasta is ready, do not drain, but use tongs to drag the pasta out of its cooking water and straight into the pot with the cabbage. Add about 1 cup of pasta cooking water, along with the pecorino and the black pepper. Toss well to combine. Add lemon juice. Taste, adjusting seasonings with more salt, pepper or lemon, if needed. To serve, scatter with walnuts and finish with more pecorino and chopped chives, if using. Good with crumbled cooked bacon also.