To use an immersion blender, turn it on, keep it fixed there and count to 10. The mayo should start to emulsify. Slowly, begin moving the immersion blender up and down, counting to 10-15 again; it should not take much longer than that. The mayonnaise will now be fully emulsified, thick, and glossy. If it is not yet, blend for another 3-5 seconds or so.
I did not have the dried chili peppers, so substituted 1 tsp. ground chipotle chili and 1 tsp. ground ancho chili.
I used Avocado Oil and increased it to make more of a marinade that was easier to coat the chicken.