In a food processor or blender, combine peanut butter, coconut milk, 3 tablespoons hot water, lime juice, brown sugar, soy sauce, ginger, garlic, sriracha and salt. Purée until smooth. Scrape into a bowl.
Divide peanut sauce in half. Set one half aside. One bowl of sauce will be used to baste the shrimp while baking. The other half will be used to serve table-side with the shrimp. Do not cross-contaminate and keep them completely separate! :-)
Shrimp & Pineapple
Heat oven to 500 degrees. In a small bowl, whisk together peanut oil, remaining 1/4 teaspoon salt and chile flakes. Thread pineapple on skewers and brush with peanut oil mixture. Place pineapple skewers on parchment lined baking sheet. Place in pre-heated oven and cook 5 minutes. Remove from oven and turn pineapple skewers over.
Thread shrimp on separate skewers and brush with the remaining peanut oil mixture. Brush shrimp on one side with the peanut sauce mixture after you've brushed them with oil.
Place shrimp on the same baking sheet away from the pineapple skewers. Place baking sheet back in oven and bake 3 minutes. Remove baking sheet from oven and turn pineapple and shrimp skewers. Brush the opposite side of shrimp skewers with the peanut sauce. Place back in oven and bake another 3 minutes.
Before removing from oven, make sure that shrimp is opaque, about 5 - 7 minutes, and pineapple is lightly caramelized, about 10 - 12 minutes total.
When done, remove from oven, place on serving plate and sprinkle skewers with chopped basil. Serve hot with reserved peanut sauce for dipping.
*1 pound of shrimp will make roughly 8.5 skewers with 4 shrimp each.