Boneless, skinless chicken thighs are grilled and topped with a smoky romesco-inspired vinaigrette. Instead of being pureed into a silky sauce, onions, bell peppers and a baguette are charred and coarsely chopped, then combined with garlic, smoked paprika, vinegar, chopped almonds and parsley to create a fresh topping.
Place the chicken on a large platter and generously season with salt and pepper. Let sit at least 10 minutes and up to 1 hour.
Whisk together the oil, paprika and garlic in a liquid measuring cup until completely combined. Put the peppers, tomatoes, onions and baguette slices on a baking sheet and generously brush with the oil mixture until completely coated, making sure to brush on bits of the garlic and paprika. Reserve the remaining oil mixture for the vinaigrette.
Prepare a grill or large grill pan for medium-high heat. Clean and oil the grill grates.
Grill the chicken until lightly charred and cooked through, 3 to 4 minutes per side (see Cook’s Note). Transfer to a cutting board and cut into 1-inch strips.
Grill the peppers and onions until lightly charred and tender, 3 to 4 minutes per side. Grill the tomatoes skin-side down until the skin is charred, about 4 minutes; do not grill the cut sides. Transfer to a cutting board and chop the onions and peppers into bite-size pieces. Grill the bread until toasted on both sides, about 1 minute per side. Transfer to the same baking sheet. Season the vegetables and croutons with salt and pepper.
Whisk the vinegar, sugar and 1/2 teaspoon salt and 1/4 teaspoon pepper into the reserved oil mixture until completely combined. Arrange the chicken on a platter and top with the peppers, onions, tomatoes, croutons and almonds. Drizzle with the vinaigrette and top with parsley. Sprinkle with red pepper flakes and serve.
If using a large grill pan, grill in batches if necessary.