Step 1

Whisk together mayonnaise, sour cream and sriracha sauce in a small bowl. Add water, a few drops at a time, to reach your desired consistency. Set aside.

Step 2

In a medium bowl, whisk together cilantro, salt, pepper, cayenne and olive oil. Add shrimp and gently toss to coat.

Step 3

Run one skewer through the fattest part of 7 or 8 shrimp (depending on shrimp size), nesting the shrimp so they are curved in the same direction. Run a second skewer through all of the shrimp near the tail. Adjust shrimp, giving each a little space, to help them cook evenly. Repeat with remaining shrimp and skewers.

Step 4

Preheat grill to medium-high heat.

Step 5

Place a large piece of aluminum foil near grill. Grill tortillas in a single layer for 30-45 seconds on each side until softened and lightly charred. Stack tortillas on aluminum foil and wrap. Place on grill off of direct heat to keep warm.

Step 6

Grill shrimp skewers 2 to 3 minutes on each side, until shrimp are pink and just cooked through. Transfer to platter along with foil wrapped tortillas.

Step 7

Assemble tacos: top one warm corn tortilla with 3 or 4 shrimp and sprinkle with chopped cabbage, radishes and cilantro (if desired). Drizzle with desired amount of shrimp taco sauce. Repeat with remaining tortillas. Serve with lime wedges and sliced jalapeño if desired.