Into the bag, combine the oil, lemon juice and zest, minced garlic, red pepper flake, ground mustard, salt, and pepper.
1/3 cup vegetable oil, 2 large lemons, zested and juiced, 2 large cloves fresh garlic, minced, 1/4 teaspoon red pepper flake, 1/2 teaspoon ground mustard, 1/2 teaspoon Himalyan or Kosher salt, 1 teaspoon freshly ground black pepper