To make the dipping sauce, in a small bowl, whisk together the mayonnaise, sriracha, and Thai sweet chili sauce. Chill until serving time.: When you whisk the mayonnaise with sriracha and Thai sweet chili sauce , notice the sauce go from matte to glossy as air incorporates, and the aroma will shift to bright, tangy notes. Chill the sauce to let flavors meld, which rounds harsh edges and allows heat to calm. If the sauce tastes too sharp, a touch more mayonnaise will smooth it. Common mistake, adding too much heat too soon, can be corrected by tempering with extra mayo, but taste in small increments.
In a shallow dish, add flour and salt and pepper to taste (I like 1/2 teaspoon and 1/4 teaspoon pepper). In a second shallow dish, add eggs and beat lightly. In a third shallow dish, combine panko and coconut. Stir to combine.: The three station setup creates rhythm and consistency. The seasoned flour should feel dry and pale, the eggs should be uniformly beaten with a slight sheen, and the panko plus coconut should be evenly distributed so each shrimp gets an even crust. This arrangement prevents clumping and cross contamination. One trap is overcrowding the dishes and getting wet spots in the panko bowl, which makes adhesion patchy; keep things tidy and use small batches.
Working with one shrimp at a time, dredge in flour and shake off excess. Dip in eggs and tap gently on side of dish to remove excess. Add to panko-coconut mixture and press gently until crumbs adhere. Transfer to a large plate and repeat with remaining shrimp (shrimp can be wrapped in plastic and refrigerated for up to 2 hours).: As you dredge each shrimp , the light dusting of flour helps the eggs cling and creates a dry surface for the crumb to grab. You will hear the soft tap when removing excess eggs , and the panko mixture should stick evenly without large clumps. Pressing gently ensures full coverage, and be mindful to keep the shrimp spaced on the plate so the coating sets. A common error is rushing and pressing too hard, which can compress the crumbs and result in a dense crust instead of a crisp shell.
Line rimmed baking sheet or large plate with 3 layers of paper towels. In a large saucepan over medium-high heat, heat canola oil until shimmering. Add shrimp in batches and fry until deep golden brown and cooked through, about 2 to 3 minutes per side (the shrimp should reach 120 degrees on an internal thermometer).: When the canola oil shimmers, it signals appropriate frying heat and you should hear a steady sizzle as the shrimp enter the oil. The exterior will quickly bloom to golden brown, and you will smell warm coconut and toasty notes. Frying in batches prevents the oil temperature from dropping, ensuring an even color and crispness. Use a thermometer to check doneness, and avoid crowding the pan which leads to greasy, soggy results. If the coating browns too fast while the interior is undercooked, lower the heat slightly and finish for a few extra moments.
Drain shrimp well on paper towels. Repeat with remaining shrimp and serve with sauce.: After frying, the moment the shrimp rest on paper towels you will see steam rise and the crust settle into a crisp texture. Let them drain briefly so excess oil moves away, preserving crunch and keeping the interior juicy. Serve the pieces hot so the contrast between crunchy shell and tender shrimp is most pronounced. A typical misstep is leaving them on paper too long; they can soften as they cool, so plate and serve promptly for the best experience.