Pickled Red Onion & Jalapenos:
1 red onion (about 12 ounces), halved lengthwise, cut thinly crosswise
5 whole small jalapenos
2 c. seasoned rice vinegar
3 tablespoons fresh lime juice
1 tablespoon course kosher salt
Place onion and jalapenos in heatproof medium bowl. Mix vinegar, lime juice, and salt in small saucepan. Bring just to boil, stirring until salt dissolves. Pour over onion and jalapenos. Let stand at room temperature at least 1 hour and up to 8 hours. (Can be made 1 week ahead. Cover and refrigerate.)
Baja Cream:
1/2 c. mayonnaise
1/2 c. sour cream
2 tablespoons. fresh lime juice
1 tsp. (packed finely grated lime peel
Pinch of salt
Whisk all ingredients in small bowl. (Can be made 3 days ahead. Cover and refrigerate.)
Tomatillo Salsa Verde:
12 ounces tomatillos, husked stemmed, divided
4 green onions, white and green parts separated
1 jalapeno chile
2 garlic cloves, unpeeled
1 1/4 c. (packed) fresh cilantro leaves
1 tablespoon (or more) fresh lime juice
Preheat oven to 375 F. Lightly oil roasting pan. Char half of tomatillos, white parts of green onions, and jalapeno directly over gas flame or in broiler. Transfer charred vegetables to prepared roasting pan. Add remaining tomatillos and garlic cloves to pan. Roast until all vegetables are soft, about 12 minutes. Cool.
Stem and seed jalapeno. Place all roasted vegetables, green onion tops, cilantro, and 1 tablespoon lime juice in blender. Puree until smooth, stopping to push vegetables down into blades several times. Transfer to medium bowl. Season with salt and more lime juice if desired.
Fish:
2 c. buttermilk
1/2 c. chopped fresh cilantro
3 tablespoons hot pepper sauce
3 teaspoons course kosher salt, divided
1 tablespoon fresh lime juice
2 pounds skinless halibut sea bass or striped bass filets, cut into 1/2x1/2-inch strips
Mix buttermilk, cilantro, hot pepper sauce, 1 teaspoon salt, and lime juice in large bowl. Add fish; toss. Cover; chill at least 1 hour and up to 3 hours.
16 corn tortillas
2 c. self-rising flour
Vegetable oil (for frying)
Preheat oven to 300 F. Wrap tortillas in foil; place in oven to warm. Whisk flour and remaining 2 teaspoons salt in medium bowl. Add enough oil to large skillet to reach depth of 1 inch. Heat oil until thermometer registers 350 F. Working in batches, remove fish from marinade and dredge in flour. Carefully add fish to skillet, cover partially, and fry until golden brown, turning occasionally, about 4 minutes. Transfer to paper-towel-lined baking sheet to drain, then transfer to oven to keep warm.
Fresh Salsa
Guacamole
Set up buffet with all taco fixings, along with fresh salsa and guacamole.