Cut tofu into 7 or 8 slices, each 1/2 in. thick and about 2 by 4 in. wide, and set in a 9- by 13-in. dish. In a food processor, whirl lemongrass, ginger, and garlic to mince. Add 2 tbsp. water and remaining ingredients; whirl to blend. Spoon marinade over tofu and turn to coat, distributing seasonings. Chill, covered, at least 3 hours, turning occasionally.
Preheat oven to 450°. Set tofu on an oiled baking sheet, brushing off seasonings with fingers. Bake tofu until browned and a little crisp, 25 to 30 minutes.
*Find this blend of fennel, star anise, cinnamon, cloves, and ginger with the spices at well-stocked grocery stores.
Wine pairing: Fresh, aromatic Poet's Leap 2015 Riesling (Columbia Valley; $20).
Make ahead: Through step 1, up 1 day, chilled.
Note: Nutritional analysis is per serving of tofu.