Cut ends from cucumbers, slice in half vertically and scoop out seeds. Cut into 2 inch sections lengthwise and then into 1/4 inch sticks. Set aside.
Prepare sauce and set aside.
Heat wok or pan over medium high heat. Add oil. When hot, add garlic and ginger and stir-fry 20 seconds. Add shrimp and stir-fry for 3 minutes. Remove from pan and add cucumbers and onions. Stir-fry for 1 minute. Add shrimp and sauce to pan. Bring to a boil, increasing heat if necessary. Stir until sauce thickens and you're done!