Step 1
Heat broiler. Place 2 large red bell peppers, cut into 3″ pieces, 1 medium onion, thinly sliced, 2 Fresno chiles, halved crosswise, 3 red Thai chiles, halved crosswise, and 5 garlic cloves on a rimmed baking sheet. Drizzle extra-virgin olive oil over and season with kosher salt; toss to combine. Broil until peppers are softened and slightly charred, 10–13 minutes.
Step 2
Transfer vegetables to a blender. Add zest and juice of 1 lemon, 2 Tbsp. apple cider vinegar, 1 Tbsp. paprika, 1 tsp. dried thyme, ½ tsp. dried oregano, and ½ tsp. freshly ground black pepper and purée until piri-piri is smooth.
Step 3
Sprinkle 3 lb. skinless, boneless chicken thighs, cut into 3″ pieces, with 1 Tbsp. Diamond Crystal or 1¾ tsp. Morton kosher salt and remaining ½ tsp. freshly ground black pepper. Heat 3 Tbsp. extra-virgin olive oil in a large Dutch oven or other heavy pot over medium-high. Working in batches if needed, cook chicken until golden, about 5 minutes per side (it will not be cooked through). Transfer to a plate.
Step 4
Add piri-piri to pot and cook, stirring often, until darkened in color and slightly thickened, about 5 minutes. Add 1 bunch Tuscan kale, ribs and stems finely chopped, leaves coarsely chopped, then return chicken to pot along with any accumulated juices. Stir in one 13.5-oz. can unsweetened coconut milk, 2 tsp. honey, and ½ cup water and bring to a boil. Reduce heat and simmer, stirring occasionally and adding up to ½ cup more water if needed, until kale is tender, chicken is cooked through, and liquid is slightly thickened, 20–25 minutes.
Step 5
Divide stew among bowls; top with sliced red chiles. Serve with toasted bread and lemon wedges.
Do ahead: Piri-piri can be made 2 days ahead; cover and chill. Stew can be made 3 days ahead. Let cool; cover and chill.