Melt butter with olive oil in a 10-inch cast iron skillet over medium heat. Add finely diced pepperoni and cook, stirring periodically, until beginning to crisp, about 2-3 minutes. Add the pepper flakes and garlic and cook, stirring, until fragrant, about 1 minute. Stir in parsley and chives and transfer to a large bowl. Stir in Parmesan cheese and set aside.

Lightly flour a work surface and divide the dough in half. Working on half at a time, roll the dough into a long strip about 4 inches wide. Using a bench scraper or pizza cutter, slice 1"x4" ribbons. Tie each ribbon into a knot and place in the bowl with the pepperoni mixture. Using your hands, gently toss to combine so that each knot is thoroughly coated then place in the skillet in a single layer. Drizzle with additional olive oil, cover tightly with plastic wrap, and sit aside at room temperature until doubled in size, about 4 hours. Alternatively, refrigerate until doubled in size, 12 to 16 hours.

When ready to bake, preheat oven to 425°F. Remove the plastic wrap and sprinkle the garlic knots with Romano cheese. Transfer to the oven and bake until golden brown and crisp, about 25 to 30 minutes.

Remove from oven and drizzle with more olive oil. Sprinkle with additional Parmesan. Serve immediately with warm marinara sauce on the side.