Top with sliced tomato and 1⁄4 cup tzaziki sauce. (health.com)
when you make tzaziki just grate your pealed cucumber, squize to get rid of reduntant fluid, add a bit of pepper, olive oil, grated garlic (you can use garlic powder or paste too), greek yogurt and mix it all, then finally add about a teaspoon of red wine vinegar, that is how my mom taught me how to make it and she is married to a greek person do not buy the mix cos it ain't the same and never will (mygreekdish.com)
Prepare tzaziki sauce: In a medium bowl, combine Greek yogurt, diced cucumber, lemon juice, dill garlic, salt & pepper. (thecountrycook.net)