Heat a saucepan on the stove over medium heat, add the soy sauce, mirin, brown sugar, garlic and ginger to the pan, whisk to combine, bring to a boil, then simmer 4-5 minutes.
In a small bowl, combine the cornstarch and water, add this to the boiling sauce and whisk together, reduce the heat to low and simmer 3-4 minutes.
Remove from the heat and set aside to cool.
Prepare the skewers by placing the end of one piece of bacon on a skewer, then add a piece of chicken and bell pepper, then wrap the bacon around the chicken and pepper and skewer the middle of the bacon.
Add another piece of chicken and bell pepper, then wrap the remaining bacon around it and skewer.
Repeat this three times per skewer for ten skewers total.
Heat a grill over medium heat.
Place the skewers on the grill for 5-7 minutes, flip and grill for an additional 5-7 minutes.
Two minutes before removing from the grill, brush the skewers with half of the teriyaki sauce.
After two minutes, remove the skewers from the grill and brush with the additional teriyaki sauce. Serve immediately.