If using wooden skewers, soak at least 30 minutes.
Add the sambal, sesame oil, and soy sauce to a mixing bowl and whisk to combine. Add the shrimp, cubed pineapple, and red onion to the bowl and toss everything together to coat it in the sauce. Thread the shrimp, pineapple and red onion onto metal skewers and arrange them on a rimmed baking sheet lined in foil.
Preheat an outdoor grill to medium high heat and lightly oil the grates.
Lightly spray the kabobs with nonstick cooking spray. Place them on the preheated grill in an even layer. Cook for 2 minutes per side, until the shrimp is cooked through and nice char marks have formed.
Remove the foil from the baking sheet and place the cooked kabobs on the clean baking sheet.
Serve with rice, butter lettuce leaves, and extra soy sauce.
Notes
Makes about 5 cups. You can serve this on kabobs or remove from the skewers.