Heat a large sauté pan over medium heat, add the olive oil and heat. Season shrimp with salt and pepper and add to the pan in a a single layer (working in batches, if needed)
Cook the shrimp
Sauté the shrimp until pink and no longer translucent, about 1½ minutes per side. Remove the shrimp to a bowl and cover. Remove and discard the tails if desired (optional).
Make scampi sauce
Add the garlic to the pan and sauté until fragrant. Add the wine to deglaze, then add the chicken stock and let the mixture reduce to about a cup, about 10 min. Stir in the lemon juice and crushed red pepper.
Add the butter
Whisk in the butter one piece at a time, continuing to whisk until combined. Stir in half of the chopped parsley and add the shrimp back to the pan.
Assemble and serve
Add the shrimp scampi mixture to a serving bowl and top with the remaining parsley. Serve with the grilled bread on the side.