Cook pasta in a large pot of salted water according to directions for just under al dente pasta (cook about 2 minutes less than listed cook time). RESERVE 1 ½ CUPS PASTA WATER JUST BEFORE DRAINING!
Meanwhile, heat a large, high sided skillet over medium heat. Add the olive oil, followed by the carrot and zucchini, saute until carrot begins to soften, about 5 minutes. Add in garlic and cook one more minute.
Place the contents of the skillet in a high powered blender, and add in the cottage cheese, marinara sauce, ½ cup pasta water, and sliced sun-dried tomatoes (if using). Blend until completely smooth.
Add the cooked pasta to the skillet and stir to coat, simmering 1-2 minutes until pasta is fully cooked. If desired, add splashes of pasta water to thin out the sauce to preferred consistency.