Rinse the clams, discarding any with cracked shells or those not closing tightly when touched.
Prepare the Fish Broth: In a medium saucepan, bring all the broth ingredients to a boil over high heat.
Cover, reduce heat to low, and simmer for 1 hour.
Strain, reserving 1 cup of broth and discarding solids.
Heat olive oil in a large shallow earthenware casserole dish or Dutch oven over medium heat.
Add pimientos and cook, stirring, for about 2 minutes.
Transfer to a blender or food processor, reserving the oil.
In the reserved oil over medium heat, add bread and garlic.
Cook until both are golden, turning the bread once and stirring the garlic.
Transfer to the blender.
Add almonds and blend until a paste forms.
Gradually add ¼ cup of the reserved broth with the motor running, then add the remaining ¾ cup broth and wine, blending until smooth.
Heat the casserole dish over medium heat.
Strain the contents of the blender into the dish, pressing with the back of a wooden spoon to extract as much liquid as possible.
Discard the solids.
Add the chili pepper, salt, and pepper.
Arrange the clams in the dish, cover, and cook until the clams open, removing each as it opens.
Discard any unopened clams.
Taste and adjust the seasoning, then remove the casserole dish from the heat.
Stir in the aguardiente and return the clams to the dish, ensuring the clam meat is covered by the sauce.
Cover and let sit for 1 to 2 hours, stirring occasionally.
Reheat the clams in the casserole dish over medium heat until heated through.
Sprinkle with parsley.
If using earthenware, serve hot in the dish, or transfer to a platter for a captivating presentation.
Notes / Tips / Wine Advice:
Wine Pairing:
Pair this elegant dish with a full-bodied Spanish white wine such as Albariño or Viura. Their rich flavors and acidity will complement the complexity of the Romesco sauce and the brininess of the clams. Alternatively, a Spanish red wine such as Rioja or Priorat would also be a delightful match, adding depth and richness to the pairing.