In a large bowl mix together the flour, 1 tsp salt, and pepper.
Pat chicken dry with a paper towel. Cut the chicken breast into 1 inch cubes. Place chicken into the flour-spice bowl and toss until well coated.
Heat the oil in a large nonstick skillet over medium-high heat for 1-2 minutes. Then, add the chicken to the skillet (leaving behind any excess flour to discard), in an even layer in the skillet. Cook for about 8-10 minutes, turning every 2-3 minutes to allow the chicken to become golden brown and crispy. Cover the pan, reduce the heat to medium-low and cook for an additional 3-5 minutes to fully cook the chicken.Use a meat thermometer to check the chicken to ensure it reaches 165°F.
Remove the chicken from the pan with a slotted spoon, leaving behind any oil in the pan.
To the pan add the garlic and butter and saute for 1-2 minutes until fragrant. Whisk in the remaining 1⁄4 teaspoon salt, brown sugar, red pepper flakes, honey and the cornstarch-water mixture and bring to a boil, then reduce the heat to low and simmer until the sauce thickens, about 2 minutes.
Add the chicken back to the pan and mix around. Add 2 tbsp water to loosen the sauce. Mix in 1 tbsp of the chopped parsley. Mix together and cook 2-3 minutes.
Serve and garnish with remaining 1 tbsp chopped parsley.