Pat the shrimp dry with a paper towel. Heat a large sauté pan over medium heat, add the olive oil and heat through. Season the shrimp on both sides with salt and pepper and add to the pan in a an even single layer (this may have to be done in batches).
Sauté the shrimp until pink and no longer translucent, about 1½ minutes per side. Remove the shrimp from the pan to a bowl and cover. Remove and discard the tails if desired (optional).
Add the garlic to the pan and sauté until fragrant, about 10 seconds. Add the wine into the hot pan to deglaze, then add the chicken stock and let the mixture reduce to about a cup, about 10 minutes.
Stir in the lemon juice and crushed red pepper, cooking for about 2 more minutes.
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.
Add the shrimp scampi mixture to a serving bowl and top with the remaining parsley. Serve with the grilled bread on the side.