Preheat oven to 375°F and line a baking sheet with parchment.
Using a food processor or a knife, chop pistachios until they are about the size of the bread crumbs. Combine pistachios with bread crumbs, shallot, garlic, lemon zest, and tarragon in a pie plate. Season with salt and pepper.
Season tofu with salt and pepper. Combine mustard and lemon juice in a small bowl. Spread mustard mixture evenly over top and sides of tofu, then press each slice into bread crumb mixture.
Place tofu, uncoated side down, on baking sheet. Sprinkle any leftover bread crumb mixture evenly on top of slices. Bake until tops are browned, about 20 minutes.
Recipes from The No Meat Athlete Cookbook: Whole Food, Plant-Based Recipes to Fuel Your Workouts and the Rest of Your Life. Copyright © 2017 Matt Frazier and Stepfanie Romine. Reprinted by permission of The Experiment.