Cut Party Potato Rolls into quarters or medium cubes and place in a large bowl. Add 1-2 tablespoons olive oil and season with salt and pepper; toss to coat. Bake on a prepared baking sheet in 350 degree F oven for 5-10 minutes or until toasted and slightly crispy.
Meanwhile, in a large bowl, combine remaining olive oil, lemon zest, lemon juice, and mint. Stir to combine.
Add watermelon chunks and gently stir to coat with dressing.
Add feta cheese, arugula, black pepper, and toasted bread cubes. Gently toss to combine all ingredients. Season to taste with flaked sea salt to add flavor and presentation. Serve chilled.