Zest a lemon to get 1/2 tsp & juice to get 3 tablespoons. Add all dressing ingredients to a mason jar. Season to taste (I add 1/2 tsp salt & 1/4 tsp pepper). Shake well until combined. Store in the fridge while prepping the salad.
Halve or quarter the tomatoes, chop the cucumbers, finely dice the red onion, roughly chop the spinach, and chop the avocado and herbs (if using).
In a large bowl, mix completely cooled quinoa and chopped spinach. Add tomatoes, cucumber, onion, avocado, and, if using, feta and herbs.If serving the same day: Add dressing to taste (as little or as much as you'd like).If meal prepping: Only dress the portion you plan to eat that day (see storage note below). Toss to combine, then taste and adjust with extra salt and pepper if needed. Serve right away.
Video
Notes
Storage:Keep the quinoa, salad ingredients, and dressing in separate sealed containers in the fridge. Mix right before serving. Once combined, this quinoa salad tastes best the same day. The quinoa will continue to soak up the dressing over time, so I only add dressing to what I plan to eat soon after dressing.Leftover dressing: It may separate or solidify in the fridge (thanks to the olive oil). Let it sit at room temperature for 20 minutes, then shake well.Nutrition Note: Nutrition information does not include optional feta cheese.