Bring enough salted water to boil. Add pasta to this and cook for 3 mins until al dente. Drain pasta and keep aside.
Heat the oil, add the garlic and onion and saute for a few minutes, till the onions soften. Add the bell peppers and saute for a few more minutes till the peppers soften.
Now add the spices and salt and mix well.
Add the tomato paste, sour cream / yogurt and enough water to make a sauce.
Now, add the cooked and drained pasta to this and mix well.
Squeeze half a lime over this, just before serving and top with some crumbled cotija cheese