Preheat grill (outdoors) or grill-pan (indoors) to medium heat.

Meanwhile, using a small skillet, add 1 Tbsp of olive oil and place over medium-high heat. Once hot, add onions; sauté for 3-4 minutes, stirring occasionally. Add garlic, continue cooking for 1-2 more minutes, stirring occasionally. Remove pan from heat.

Transfer onions and garlic into a large mixing bowl. Add lamb, cumin, salt, pepper, rosemary, ketchup and Swiss cheese; stir until well combined. Shape into 6 patties, leaving a slight indention in the center of each patty. Brush patties with remaining 1 Tbsp of olive oil.

Place patties on grill or grill pan; cook over medium heat until fully cooked (~4-5 minutes per side). (Note: If you don’t have a grill pan, then a cast iron skillet is a great way to cook these sliders!)

Place cooked patties in Flatout Foldits and top with spoonful of Feta Tzatziki Sauce.

{Optional} Garnish with additional fresh rosemary before serving.

Slice the cucumber lengthwise and use a spoon to scrape out the seeds. Using a medium grater, grate the cucumber into a bowl. Using several paper towels, press the grated cucumber firmly to remove as much liquid as possible.

Add all of the remaining ingredients (yogurt, sour cream, feta, garlic, lemon juice, vinegar, dill, salt and pepper) and mix until well blended. (See note.)

Cover and refrigerate for several hours. (Tip: This dip will taste much better if you refrigerate it overnight!)