Prepare the Shrimp: Preheat your grill or skillet over medium-high heat. In a bowl, toss the shrimp with melted coconut oil, chili powder, salt, and pepper. Grill the shrimp for 2-3 minutes on each side, or until they are pink and slightly charred. Remove from heat.
Make the Pineapple Salsa: In a bowl, combine diced pineapple, red onion, cilantro, lime juice, jalapeño (if using), and salt. Mix well and set aside.
Prepare the Guacamole: In another bowl, mix mashed avocados, lime juice, diced tomato, chopped onion, salt, and pepper until well combined.
Assemble the Tostadas: Spread a generous layer of guacamole on each tostada shell. Top with grilled shrimp and a spoonful of pineapple salsa. Sprinkle toasted shredded coconut over the top.
Serve: Offer lime wedges on the side for squeezing over the tostadas. Enjoy immediately for the best texture and flavor