Combine in a medium saucepan over medium heat: coconut milk, peanut butter, brown sugar, rice vinegar, curry powder, salt. Stir, then bring to a boil. Reduce heat to low, cook 20 minutes, stirring occasionally until thickened and creamy. Set aside.
Heat oil in a nonstick skillet to medium high heat. Season shrimp with sea salt and place on skillet for approximately 3 minutes per side or until shrimp are cooked through (shrimp are fulling cooked when they reach 140F.
Top shrimp with cilantro (optional) and serve immediately with peanut sauce.