-
1
Put oven rack in middle position and preheat oven to 400u00b0F.
-
2
Heat butter in a 10-inch heavy skillet over moderate heat until foam subsides, then cook flour, stirring, until golden brown, 3 to 4 minutes. Transfer to a small bowl.
-
3
Puree onion, garlic, peppers, sugar, vinegar, and 1/2 teaspoon salt in a blender until smooth, adding 1 to 2 tablespoons water if needed to facilitate pureeing.
-
4
Heat 2 tablespoons oil in a large nonstick skillet over moderate heat until hot but not smoking, then cook puree, stirring, until thickened, 3 to 4 minutes. (Don't worry if mixture turns blue-green; this sometimes results from the interaction of vinegar and immature garlic.) Reserve 5 tablespoons puree in a small bowl (for coating lamb) and transfer remainder to another small bowl (to be served on the side with lamb).
-
5
Sprinkle lamb with remaining tablespoon salt. Heat remaining tablespoon oil in cleaned 10-inch skillet over moderately high heat until hot but not smoking, then brown lamb 1 rack at a time, turning over once, about 4 minutes per rack. Transfer racks to a large roasting pan, arranging with bones curving downward.
-
6
Spread 1 1/2 tablespoons
-
7
puree over meaty part of each rack of lamb, excluding ends. Stir parsley into
-
8
mixture, then pat mixture onto lamb (over puree) to coat, pressing gently to adhere.
-
9
Roast lamb until thermometer inserted diagonally 2 inches into center (do not touch bone) registers 125u00b0F (for medium-rare), 20 to 25 minutes. Transfer to a cutting board and let racks stand 15 minutes (internal temperature will rise to about 130u00b0F).
-
10
Cut each rack into chops and serve remaining puree on the side.
