Preheat oven to 350°F.
Sauce: Combine the water and cornstarch in a small bowl, whisking with a fork to form smooth slurry. Place all remaining ingredients in a small pot and simmer for 10 minutes. Whisk in the cornstarch slurry and continue to cook another five minutes until the sauce has thickened slightly. Remove from heat and transfer to bowl. Cool in refrigerator until ready to serve.
Chicken: Season chicken breast with salt and place in a baking tray. Bake for 10 to 12 minutes until completely cooked. Let cool, and then cut into quarter-inch slices. Chill until ready to serve.
Lettuce Wraps: Take one or two lettuce leaves in your hand and spread a small amount of mayo. Add a few slices of chicken and cucumber. Sprinkle with cashews. Add as little or as much sweet chili sauce you want. Enjoy!