Step 1

Bring a large pot of salted water to a boil.

Step 2

Add spaghetti and cheese rind, if using, and cook until al dente, about 11 minutes. Drain, reserving 1 cup of the cooking liquid.

Step 3

Meanwhile, place bacon in a large skillet over medium heat and cook until crispy, turning occasionally, about 6 minutes. Transfer to a plate, leaving fat in the skillet.

Step 4

Add garlic to the skillet and cook until fragrant, about 1 minute. Remove from heat and stir in miso.

Step 5

Transfer drained pasta (no need to remove the cheese rind) to the skillet with garlic and miso.

Step 6

Place over medium-low heat and stir in arugula and ¼ cup of the reserved pasta cooking liquid. Cook, stirring until arugula just begins to wilt.

Step 7

Alternate stirring in tablespoons of reserved cooking liquid with tablespoons of cheese; stir in more cooking liquid as needed until you have a creamy sauce.

Step 8

Stir in bacon and half of the pepper. Transfer to a warmed bowl or platter, and garnish with remaining pepper.