Mix all Tzatziki sauce ingredients together and place back in the fridge.
Place quinoa and chicken broth in the pot of a pressure cooker. Place the chicken on top, sprinkle with Greek seasoning and salt & pepper. Close the pressure cooker, set knob to seal, cook on high pressure for 6 minutes with a quick release.
Assemble the meals with equal portions of the quinoa and chicken and then add the remaining toppings. Add a couple spoonfuls of Tzatziki sauce to each and then serve or cover and save for later. (Can be eaten warm or cold. If planning to reheat, leave off the Tzatziki sauce and add after heating.)