Peel and devein the shrimp. Place in a bowl and sprinkle with salt and pepper. In a large and heavy saute pan set over medium-high heat, let the butter melt. Once it starts to sizzle, add the garlic. Stir and cook for 10 to 15 seconds, until the garlic becomes fragrant. Incorporate the shrimp, making sure that the pan is not over crowded, and let them brown on one side and then the other, just for about 1 to 2 minutes per side. Don't let them over cook, they should brown on the outside, but barely cooked through.