Brush tofu with 1 tablespoon olive oil, season with grated lemon peel, and set aside for 30 minutes. Grill the tofu slices for 2-3 minutes per side – the tofu is very delicate, so turn it carefully. Set aside when grilled.
Boil the pasta according to package instructions, drain, and set aside.
Meanwhile, heat the remaining olive oil in a large skillet over medium-high heat. Add sliced mushrooms and sauté for 5 minutes, stirring occasionally. Reduce the heat, add minced garlic, and season with salt and pepper. Cook for 1 minute, then add pasta and arugula, and toss everything together. Remove from the heat.
Divide the pasta between 2 serving bowls. Top with the tofu, scatter with toasted pine nuts, and serve.