Use a large knife to finely mince the chipotle peppers, then use the side of the knife to grind them into a paste as finely as possible.
In a medium bowl, stir together 2 tablespoons of the mashed chipotle peppers with the grated garlic, mayonnaise, cumin, and kosher salt. (Taste and if desired, you can add more chipotle for an even spicier kick.)
For a perfectly creamy sauce, use a spatula to press the sauce through a fine mesh strainer. Stores up to 2 weeks refrigerated.