I’ve been making variations of this succulent sauce since 1997. Romesco sauce is from Catalonia and is usually served over fish or other meat. It is frequently made with both almonds and hazelnuts as well as stale bread crumbs. My version is slightly different, but still hits those same taste notes. I usually serve it over grilled veggies, spread on tortillas topped with avocado and salad greens, dolloped on top of slices of baguette, thinned out and drizzled over orzo, etc.
I nearly always have everything for this in my kitchen, which means that even though we've been pretty homebound these last few months, I can usually make this without a trip to the store. In my freezer I always have almonds (if you don't already, do store your nuts in the freezer to prevent them going rancid) and bags of red bell peppers that I roasted and froze the previous summer. If you don’t have sherry vinegar, substitute a light balsamic. If you don’t have smoked paprika, just use regular paprika.
In a food processor or blender, combine almonds, bell pepper, garlic, tomatoes, salt, and paprika. Pulse until fairly well pulverized.
With the machine running, gradually pour in the sherry vinegar, then the olive oil. Continue to pulse until fully blended. If the sauce is too thick, add a little bit of water or, if you like it richer, more olive oil.