Pour the pinto beans into a colander and rinse them under cool water until the water runs clear. This removes extra starch that can make the dip too thick or taste canned.
Add the ingredients to the blender: rinsed beans, jalapeño brine, melted butter, garlic powder, cumin, smoked paprika, onion powder, and salt. Blend on high for about one minute. Stop halfway to scrape down the sides. The dip should be smooth and creamy, with no visible bean chunks.
Add water one tablespoon at a time. Blend briefly after each addition until the dip is smooth and scoopable. It should not be runny but soft enough to spread easily.
Pour the blended dip into a small saucepan. Warm it over low heat for about three to five minutes, stirring often, until heated through. Taste the dip and add more salt or jalapeño brine if you want it tangier or saltier. Transfer the dip to a serving bowl and serve warm with Fritos corn chips or tortilla chips.