Whisk all of the marinade ingredients together in a small bowl. Place pork/chicken/etc cubes in a Ziploc bag and pour in the marinade. Seal the bag and toss to coat evenly with the marinade, then open the bag and reseal, removing as much air as possible. Place bag in the refrigerator for at least two hours to overnight (overnight recommended for optimal flavor!).
Mix all the tzatziki ingredients together in a bowl until well combined. Cover and place in the refrigerator for at least two hours to overnight (overnight is preferable).
Put pork/chicken/protein on skewers and grill until they are browned on all sides and cooked through, about 8 to 12 minutes, turning 4 times during cooking. Remove the skewers to a plate and allow to rest for 5 minutes.
While the meat rests, prep your serving options: salad greens, veggies, heat grains/bread/cauliflower rice then serve with a large dollop of tzatziki sauce and enjoy!