Lamb Dumplings with Cucumber Vinegar Dipping Sauce

Name: Lamb Dumplings with Cucumber Vinegar Dipping Sauce
Ingredients: 1/2 onion, finely chopped; 3 garlic cloves, minced; 1 potato, peeled and finely diced; 1 1/2 teaspoons cinnamon; 1 teaspoon cumin; 1 pound ground lamb; 1/2 teaspoon coriander; 1 teaspoon salt; 1/2 teaspoon freshly ground black pepper; 1 bunch mint, chopped; 1 packet circular potsticker wrappers; Neutral oil for pan-frying; 1 large cucumber; 3 tablespoons rice vinegar