Bring water and bouillon cube to a boil in a pot until bouillon is dissolved; decrease heat to low. Whisk tahini, soy sauce, honey, garlic, and ginger into bouillon mixture until smooth. Keep sauce warm over low heat.
Heat butter in a skillet over medium heat; cook and stir chicken until no longer pink in the center, 5 to 10 minutes.
Whisk flour into tahini sauce until thickened, 2 to 3 minutes. Add cooked chicken to tahini sauce and toss to coat.
