Wrap one piece of bacon around each hot dog and secure on each end with a toothpick. Refrigerate until ready to grill.
Open cans of beans and heat to a simmer. Drain beans in a strainer over a medium mixing bowl, keep warm.
Toss diced tomatoes, onions, cilantro together, set aside.
Grill bacon wrapped hot dogs over medium heat until bacon is crispy on all sides, but not burned. Make sure to cook slowly and turn the dogs often so that the hot dogs are heated through by the time the bacon crisps, about 10 minutes.
Spoon the mayonnaise into a ketchup type squirt bottle. Thin with milk, a little at a time, if necessary.
Dice avocado and toss with lime juice. Toss into the tomato mixture.
Assemble the hot dogs by spooning beans into the bottom of the hot dog bun. Add the hot dog and top with the avocado pico de gallo.
Drizzle Sonoran Hot Dogs with mayonnaise.
Garnish with a sprig of cilantro.