Bring a large pot of well-salted water to a boil over high heat.

Meanwhile, coarsely chop the garlic. Sprinkle it with 1/2 teaspoon salt and using the flat side of a chef's knife mash it to a paste.

In a large bowl, stir the garlic paste, roasted peppers, tomatoes, parsley, 3 tablespoons of the oil, the capers, and the pepper flakes.

Heat the remaining 1-1/2 tablespoons oil in a 10-inch skillet over medium heat. Add the breadcrumbs and toast, stirring frequently, until the smaller crumbs are golden brown, 2 to 3 minutes. Transfer to a plate and sprinkle with salt.

Cook the linguine in the boiling water according to package directions until al dente. Reserve about 1/4 cup of the pasta water and drain the pasta in a colander. Add the hot pasta to the red pepper mixture, toss to combine, and add just enough of the reserved pasta water to moisten (you won't need it all). Add the cheese, toss well, and season to taste with salt. Serve topped with the breadcrumbs and additional cheese.