If frozen, thaw the shrimp. You can either thaw the shrimp in the refrigerator overnight, or place in a strainer set in a bowl and run room temperature water (not hot water!) over them for a few minutes to break apart and thaw. Then drain and pat well with paper towels.
Marinate the shrimp. Drizzle the shrimp with the olive oil and toss with the garlic, kosher salt, black pepper, and red pepper flakes. Set aside for the flavors to meld for 20-30 minutes.
Cook the shrimp in batches. Heat a non-stick skillet over medium-high heat. Drizzle the pan with 1 tablespoon of the olive oil and add the shrimp one at a time, careful not to overcrowd the pan, cooking in two batches. Cook for 2 minutes on one side, then flip the shrimp and cook just until opaque, then transfer to a bowl. Toss the cooked shrimp with the pesto and set aside.
Cook the garlic and tomatoes. Reduce the heat slightly and add the oil and garlic from the original shrimp bowl along with the tomatoes to the skillet. Cook for 4-5 minutes, turning the tomatoes and garlic so the garlic doesn’t burn and get bitter. Take the skillet off the heat and set aside.
Assemble your salad. Add the arugula to a bowl, drizzle with the remaining olive oil, a generous squeeze of lemon juice, and toss with your fingers to coat. Shave the Parmesan over the arugula, top with the beans and the tomatoes with all of the garlicky bits from the skillet. Add the shrimp. Season with more kosher salt and freshly ground black pepper to taste and eat it up.