Prepare the Vinaigrette: Combine olive oil, balsamic vinegar, Dijon mustard, minced garlic, salt, and pepper in a bowl or jar. Whisk or shake until emulsified. Let sit for 10 minutes.

Cook the Orzo: Boil salted water, add orzo, and cook for 7-9 minutes until al dente. Drain and rinse under cold water.

Prepare the Sun-Dried Tomatoes: Soak tomatoes in hot water for 5 minutes, then chop into bite-sized pieces.

Assemble the Salad: In a bowl, layer spinach, warm orzo, and chopped sun-dried tomatoes. Crumble feta on top.

Dress the Salad: Drizzle vinaigrette over the salad mix and toss gently to combine.

Serve or Store: Enjoy warm or refrigerate in an airtight container for up to 4 days, keeping spinach separate until serving.