Step 1

Preheat oven to 350°. Working in 3 batches, pulse mushrooms in a food processor until no pieces are bigger than ¼". Transfer to a lightly oiled parchment-lined rimmed baking sheet. Wipe out and reserve food processor.

Step 2

Add chickpeas to sheet and toss to combine. Bake, tossing once halfway through, until chickpeas are slightly darkened and mushrooms have shrunk and are browned, 35–40 minutes. Let cool. Keep oven on.

Step 3

Meanwhile, bring chile, soy sauce, honey, and 1 Tbsp. vinegar to a boil in a small saucepan. Reduce heat to medium-low and simmer, stirring frequently, until slightly thickened and foamy on top, about 10 minutes. Let cool.

Step 4

Pulse eggs, ginger, garlic, panko, chopped scallion greens, ⅓ cup cilantro, and 3 Tbsp. oil in food processor until fully incorporated. Add chickpea-mushroom mixture and 1 tsp. salt and pulse until no pieces are bigger than ¼". Transfer chickpea mixture to a large bowl and chill at least 25 minutes to firm up.

Step 5

Oil a new sheet of parchment and place on baking sheet. Roll chickpea mixture with your hands into golf-ball-size balls (about 1½"). Arrange balls on prepared sheet and brush with about one-quarter of spicy soy glaze mixture. Bake meatballs until firm and slightly darkened, 18–20 minutes.

Step 6

Meanwhile, toss celery (with leaves) and remaining scallions, ½ cup cilantro leaves, and 2 Tbsp. vinegar in a medium bowl; season with salt.

Step 7

Arrange meatballs on a platter and drizzle with sauce. Scatter celery salad over. Serve remaining sauce alongside.

Step 8

Do Ahead: Soy glaze can be made 1 day ahead. Cover and chill. Meatballs can be formed 2 days ahead. Cover with plastic wrap on a rimmed baking sheet and chill.