Bring a large pot of salted water to a boil and cook the pasta until just al dente, about 8 minutes. Drain and set aside.
While the pasta cooks, heat 1 tablespoon of olive oil in a skillet over medium heat. Add the minced garlic and sauté until fragrant and golden, about 30 seconds to 1 minute.
Add the thawed spinach to the skillet and cook until wilted, about 2-3 minutes. Season lightly with salt and pepper if desired.
In a large mixing bowl, combine the cooked pasta, tomato sauce, sautéed greens, nutritional yeast, and a splash of olive oil. Mix until well coated and evenly combined.
Transfer the mixture into your greased baking dish, spreading it out into an even layer.
In a small bowl, toast the breadcrumbs in the remaining 1 tablespoon of olive oil until golden and crispy, about 3-4 minutes. Sprinkle the toasted breadcrumbs evenly over the pasta.
Place the baking dish in a preheated oven at 180°C (350°F) and bake uncovered for 20–25 minutes, until bubbling around the edges and the top is golden brown with crispy breadcrumbs.
Remove from the oven and let rest for 5 minutes to allow the dish to set and cool slightly.
Serve warm, scooping portions that showcase the bubbling sauce and crunchy topping. Enjoy this cozy, veggie-loaded baked pasta!