This serves 2 hungry people as a main course or 4 people along with other side dishes.
Slice tofu into pieces 1/2 inch x 1/2 inch x 2 inches. Place on triple layers of paper towels, top with another triple layer of paper towels and press out excess moisture.
Heat oil in a large skillet or wok over medium-high heat. Add tofu, and cook for about 5 minutes, turning over once or twice, until golden brown. Using a slotted spatula, remove pieces to a paper towel-lined plate to drain. Set aside.
Add garlic and lemongrass to skillet, and stir-fry for 1 to 2 minutes, or until garlic becomes fragrant. Using a slotted spoon, remove garlic and discard. Leave lemongrass in skillet.
Cut asparagus spears into 11/2-inch lengths. Add scallions, asparagus and sugar snap peas to skillet, and stir-fry for 1 minute. Add sugar, salt and chili paste, and stir. Add mushrooms and soy sauce, bring to a boil, cover and cook for 2 minutes, or until mushrooms are tender and have released their juices. Serve hot over rice, and garnish with cilantro.