Bring a small pot of water to a boil. Add peas to the water, and cook for 3 minutes. Drain peas and transfer to food processor. Add olive oil, parmesan cheese, garlic, and red pepper flakes, and blend until the mixture forms a paste. With the machine running, slowly add the olive oil until well incorporated, about 1 to 2 minutes. Season with salt and pepper.

Toast baguette slices under broiler or on a grill pan until golden brown on both sides. Spread about 1 tablespoon of the pesto on each of the toasts. Top with parmesan cheese shavings if desired and serve.