01 - In a medium saucepan set over medium heat, combine the whole milk and softened cream cheese. Stir continuously with a whisk or wooden spoon until the cream cheese has fully melted and the mixture is completely smooth with no lumps remaining.
02 - Gradually add the shredded cheddar and Monterey Jack cheese, one handful at a time, stirring constantly after each addition. Continue stirring until every addition has fully melted and the dip reaches a velvety, creamy consistency.
03 - Stir in the finely chopped jalapeño, diced tomato, chives or green onions, minced garlic, ground cumin, smoked paprika, salt, and black pepper. Mix thoroughly to distribute all flavors evenly throughout the dip.
04 - Continue cooking for an additional 3 to 5 minutes, stirring frequently to prevent scorching on the bottom, until the dip thickens slightly and coats the back of a spoon.
05 - Transfer the finished dip to a warm serving bowl. Present immediately alongside tortilla chips, crusty bread, pretzels, or an assortment of fresh vegetable sticks such as celery, carrots, and bell peppers.