Garganelli with Cultured Black Garlic Butter
For the butter...
In a mason jar, add 3 tablespoons of cultured buttermilk to (a little less than) 32 ounces of heavy cream. Stir to combine and loosely cover the jar with the top (don't close it too tightly). Let the cream sit at room temperature for 24-48 hours until significantly thickened. It should smell tangy!
Once thickened, line a medium bowl with a double layer of cheesecloth, allowing an overhang.
Transfer the cream mixture to a food processor. Pulse on high until the buttermilk and butterfat separate: it should look like cottage cheese and won't take long. Do not over-mix! Carefully transfer the separated cream to the cheesecloth-lined bowl to drain the buttermilk, which can be reserved for another use.
Using the cheesecloth, squeeze as much excess buttermilk out as possible over the bowl, then transfer the buttermilk to another container. Remove and discard the cheesecloth—you'll be left with a butterball.
Fill the bowl with enough cold water to cover about half of the butterball. Using a wooden spoon, press into the butterfat in all direction to extract additional buttermilk. Drain the water and repeat the process 3-5 times until the water runs clear. Pat dry and return to the (clean) food processor.
Peel and roughly chop a few cloves of black garlic (roasted garlic would be a great alternative, or any other mix-ins you prefer!). Pulse the black garlic and a sprinkle of flaky salt with the butterball until smooth and evenly dispersed but not entirely homogeneous. Taste and adjust seasoning as needed. Transfer butter to an air-tight container and refrigerate for up to 3 weeks.
For the pasta...
Make a batch of your usual egg pasta dough (or see my recipe here). Working in batches, roll the pasta dough into a semi-thin sheet, about setting 5 or 6 on my Marcato/KitchenAid—I prefer my garganelli rolled thicker so it holds its shape and doesn't deflate.
Cut the pasta sheet into 3-centimetre (about 1.25-inch) squares. Place each square diagonally on the gnocchi board. Curl the bottom point of the square around a wooden dowel, then roll the dowel forward quickly and firmly to form the ridges until the edges seal. Remove the dowel and repeat!
Cook the garganelli in well-salted water. Melt a few tablespoons of the black garlic butter in a pan over medium heat. When the pasta is nearly cooked, add a small ladle of pasta water to the butter and stir vigorously to emulsify. Transfer the pasta directly to the butter sauce, toss to coat, and allow to cook for another minute to absorb the flavor. Serve immediately and enjoy!