Step 1

Preheat oven to 450°. Toss tomatillos and oil on a rimmed baking sheet; season with salt and pepper. Roast, tossing once, until skins are blistered in spots and beginning to separate from flesh, 15−20 minutes. Let cool, then purée in a food processor until smooth; transfer to a medium bowl. Stir in mayonnaise and lemon juice; season with salt and pepper. Cover and chill.

Step 2

Place eggs, crabmeat, lemon zest, lemon juice, chives, crème fraîche, mayonnaise, piment d’Espelette, and ⅔ cup panko in a medium bowl; season with salt and pepper. Gently stir until mixture comes together (it will be slightly wet). Cover and chill until cold, about 30 minutes.

Step 3

Place remaining panko in a shallow bowl. Using wet hands, form about 2 Tbsp. crab mixture into a ¾"-thick cake. Repeat to make about 20 cakes. Coat in panko, pressing gently to adhere.

Step 4

Heat 1 Tbsp. oil in a medium skillet over medium. Working in a few batches and adding 1 Tbsp. oil to skillet in between, cook until deep golden brown, about 2 minutes per side. Transfer to paper towels to drain; season with salt. Serve crab cakes with mayo and lemon wedges.