Sauce: Combine all of the ingredients into a bowl and mix. Keep cool until ready to serve.
Season the salmon on all sides with cumin, chili powder, sea salt, and pepper.
Add oil to the griddle and sear the salmon until crisp and brown on both sides, about 2 to 3 minutes per side. Set aside until ready to serve.
To assemble: Add a leaf of lettuce to the bottom of a toasted brioche roll and layer on with a cooked piece of salmon, 2 slices of heirloom tomatoes, 2 strips of halved bacon, micro greens and 1 tablespoon of the dill caper sour cream, followed up with the top toasted brioche roll.
Repeat the process 11 more times with the remaining ingredients.