Make the Guava sauce/marinade first.

Combine everything in a medium saucepan except for the cornstarch slurry. Stir until combined then bring to a boil. Lower to a simmer and cook for 15-20 min until slightly reduced. Strain out the garlic and ginger root solids then return to the pan and bring back to a simmer.

Combine the cornstarch and water to create the slurry then add to the sauce, stirring well while its added in. Continue cooking the sauce until it is thickened. Tasted and add more sriracha if a spicier sauce is desired. Let cool completely before marinating chicken

Place prepared chicken into a large bowl and pour over a cup to a cup and a half of the sauce. Mixing well. Marinate for 4-6 hours up to overnight. Bring to room temperature when ready to grill.

Preheat the grill to medium low.

Skewer the chicken and green onion alternating with a piece of chicken and three pieces of the green onion. Skewer through each chicken piece 2-3 times folding it as you go. Each skewer should have 4 pieces of chicken and three bundles of green onion. Repeat with remaining chicken and green onions.

Grill skewers on low. Start basting with the guava sauce when the chicken is about halfway cooked. With the higher sugar content in the sauce from the juice, honey and ketchup the sauce will tend to char before the chicken is cooked. Baste every time you flip the skewers, every few minutes. The skewers should take about 25 min to grill. More for thicker pieces of chicken.

If your grill has hot spots, keep the skewers over the cooler parts. You want nice, even cooking.

Once cooked, transfer to a serving platter and liberally brush the chicken with more sauce.

Serve with sticky rice sprinkled with soy sauce and some green onion slices.