In a bowl, combine chicken, shandy, lemon juice, garlic, soy sauce, chili paste and corn starch.
In a hot wok over medium-high heat, add 1-2 tsp oil. Add onions and stir-fry 2 minutes. Add peppers and celery and continue to stir-fry for 2-3 minutes. Remove from wok.
Strain and reserve marinade. Add chicken to wok and stir-fry 3-4 minutes.
Return vegetables to wok. Return marinade to wok. Stirring constantly, bring to a gentle boil.
Boil 1 minute, until sauce thickens. Remove from heat.