First make your romesco sauce. Add all your ingredients into a blender and pulse until smooth. Taste and add more salt if necessary.
Set aside until shrimp is ready.
To make shrimp, season with all your seasonings, and in a very hot cast iron, add a bit of oil and pan sear the shrimp, flipping once until nicely browned on each side but not overdone.
Top your romesco with your pan seared shrimp, top with more olive oil, sprinkle with red chili flakes it desired and garnish with parsley.
Serve with toasted bread.