Drain the tofu. Press it for 30 minutes: wrap in clean towels or paper towels, set a plate on top, and weigh it down with a heavy pan or cans. Longer pressing gives firmer, crispier tofu.
Cut the pressed tofu into 3/4-inch cubes or slabs. Pat each piece dry with fresh towels — surface moisture is what keeps tofu from browning.
Toss the tofu with the minced lemongrass, garlic, soy sauce, sugar, 1 tbsp oil, pepper, and chile. Let it sit 15 minutes while you prep the herbs.
Heat 2 tbsp oil in a large nonstick or well-seasoned skillet over medium-high heat. Sear the tofu in a single layer, undisturbed, about 3 minutes per side, until golden and crisp on at least two sides. Work in batches if the pan is crowded.
Turn off the heat, squeeze over the lime juice, and toss with the fresh herbs just before serving — the residual heat wilts them slightly without killing them.
Serve over rice with extra herbs and lime wedges.