Cook pasta according to package directions. Drain and rinse with cold water. Pour into a large bowl. Add black beans, corn, bell pepper, cilantro, green onions, and cherry tomatoes. Toss.
To make dressing: In a food processor or blender, combine avocados, green onions, garlic, cumin, Greek yogurt, lime juice, milk and taco seasoning. Pulse until combined and creamy. If too thick, add a little more milk. Salt and pepper to taste.
Serve southwest pasta salad either by drizzling with dressing (as shown) or toss to coat pasta and veggies. Enjoy!
To make ahead: Mix all ingredients together and toss in the avocado lime dressing to evenly coat the pasta and veggies. Cover with plastic wrap or lid and store in fridge until ready to serve.
To store: Place leftovers in an airtight container and store in the fridge for up to 3 days. Sometimes I save a little extra of the dressing and mix it in before enjoying again so that the pasta doesn't dry out.