Mushroom Kasha Burgers with Chipotle Mayonnaise

Preparation

1. Step 1

   Bring water to a boil in a 1 1/2-quart heavy saucepan, then stir in the kasha. Cover and reduce the heat to low, then cook until the kasha is tender and the water is absorbed, about 10 minutes. Transfer to a bowl and cool. Break one-third of the mushrooms into a food processor and pulse until finely chopped, then transfer to a bowl. Repeat with the remaining 2 batches of mushrooms, transferring to the bowl.

   Step 2

   Cook the onion and bell pepper in the butter in a 12-inch heavy skillet over medium heat, stirring occasionally, until softened, about 5 minutes. Add the chopped mushrooms, the garlic, 3/4 teaspoon salt, and 1/2 teaspoon pepper and cook over medium-high heat, stirring occasionally, until any liquid the mushrooms give off is evaporated and the mushrooms begin to brown, 8 to 10 minutes. Transfer the mixture to a large bowl, then stir in the kasha, parsley, soy sauce, and 1/2 cup bread crumbs until combined well. Cool 10 minutes, then stir in the egg until combined well.

   Step 3

   Line a platter with foil. Spread the remaining 1 cup bread crumbs in a shallow baking dish. Form one-fourth of the mushroom mixture (about 3/4 cup) into a 3/4-inch-thick patty (3 1/2 inches in diameter), then dredge in bread crumbs, knocking off excess, and transfer to the platter. Form and dredge 3 more patties, transferring each to platter. Chill the patties, loosely covered with plastic wrap, 1 hour.

   Step 4

   Heat the oil in a clean 12-inch heavy skillet over medium-high heat until it shimmers, then fry the patties, turning over once, until deep golden, about 4 minutes total. Transfer the patties to paper towels to drain (patties will be soft).

   Step 5

   Meanwhile, whisk together the mayonnaise and chipotle sauce. Spread the bread with chipotle mayonnaise and sandwich each mushroom patty between 2 slices.

2. DO AHEAD

   Step 6

   The PATTIES can be formed, without bread-crumb coating, 12 hours ahead and chilled, covered.