Heat a heavy skillet over medium-high heat and brown the sausage, breaking up any large clumps. Drain on paper towels.
In a large microwave-safe bowl, add the Velveeta, sausage, Rotel, and milk, and microwave on high for three minutes.
Stir the mixture and microwave for an additional three minutes or until thoroughly melted.
Transfer the dip to a crock pot set on low.
Top with the avocado, tomato, onion, and cilantro, and serve with warm tortilla chips.