While your quinoa cools to room temperature, prepare all vegetables for maximum efficiency. Dice the plum tomatoes into bite-sized chunks, peel and dice the cucumbers into similar-sized pieces, and dice the red bell pepper into uniform 1/2-inch pieces—this consistency matters for even flavor distribution in every bite. Mince the shallot finely, pit and halve the kalamata olives, and chop the fresh parsley. Having everything prepped before you start assembling ensures the salad comes together quickly and prevents the vegetables from sitting around and becoming watery.

In a small bowl, whisk together the red wine vinegar, dried oregano, salt, and freshly ground black pepper until the salt dissolves and the oregano releases its flavor. Slowly stream in the olive oil while whisking constantly to create an emulsion—this technique ensures the dressing coats evenly throughout the salad rather than pooling at the bottom. I find that letting this sit for 2-3 minutes allows the oregano to bloom and deepen the flavor profile of the entire dish.

Cut or crumble the feta cheese into bite-sized pieces—I prefer crumbling it by hand to create irregular, rustic chunks that distribute more naturally throughout the salad. In a large bowl, combine the cooked and cooled quinoa with all the prepared vegetables from Step 1, the capers, and the feta. Pour the vinaigrette from Step 2 over the top.

Gently toss all ingredients together until the quinoa and vegetables are evenly coated with the vinaigrette and the feta is distributed throughout. Taste and adjust seasoning as needed—the salad can handle a bit more salt or pepper if desired. Serve immediately at room temperature, or refrigerate for up to 2 hours if you prefer a chilled salad (the flavors will meld beautifully over time).