Prep the kimchi and aromatics. Chop the kimchi into small bite-size pieces. Mince the garlic and finely chop the shallot or onion. Slice the scallions and set aside for garnish.

Boil the pasta. Bring a large pot of well-salted water to a boil. Cook pasta until just shy of al dente. Reserve 1 cup of pasta water, then drain.

Build the flavor base. In a large skillet over medium heat, warm the oil and add butter. Sauté the shallot until translucent, 2–3 minutes. Add garlic and cook 30 seconds until fragrant.

Add kimchi and caramelize slightly. Stir in the chopped kimchi and cook 2–3 minutes. Let some edges sizzle and brown—this deepens the flavor.

Stir in gochujang. Add 1 tablespoon gochujang first and cook it into the kimchi for 1 minute. If you like more heat and color, add the second tablespoon.

Deglaze and enrich. Pour in the kimchi juice and a splash (1/4 cup) of pasta water to loosen. Stir in the heavy cream, soy sauce, and fish sauce (if using). Reduce heat to medium-low and let it gently simmer 2–3 minutes until slightly thickened.

Taste and balance. The sauce should be creamy, savory, and tangy. If it’s too sharp, add 1 teaspoon sugar or honey. If it feels heavy, brighten with 1 teaspoon rice vinegar. Adjust salt and pepper.

Toss the pasta. Add the drained pasta to the skillet. Toss vigorously, adding splashes of pasta water as needed to create a silky, glossy coating. Cook 1–2 minutes until the pasta finishes in the sauce.

Finish and garnish. Off the heat, swirl in a small pat of butter for shine. Sprinkle with scallions. Add grated Parmesan if you like a saltier, cheesier finish.

Serve hot. Plate immediately. The sauce tightens as it cools, so enjoy it right away.