In a medium jar, combine 1/4 cup of extra virgin olive oil, 3 tablespoons of balsamic vinegar, 1 minced garlic clove, 1 teaspoon of Dijon mustard, and salt and pepper to taste. Secure the lid and shake vigorously until the ingredients are well mixed and emulsified. Set the vinaigrette aside to let the flavors meld while you prepare the salad.

Bring a large pot of salted water to a rolling boil. Add 1 cup of orzo pasta and cook for 7-9 minutes, stirring occasionally, until al dente. Once cooked, drain the orzo in a colander and rinse with cold water to halt the cooking process. Ensure that it cools slightly.

While the orzo is cooling, chop 1/2 cup of sun-dried tomatoes into bite-sized pieces. Place them in a small bowl and cover with hot water, allowing them to soak for about 5 minutes. Drain thoroughly and set aside.

In a large mixing bowl, place 4 cups of fresh baby spinach as the base. Add the warm, drained orzo, the soaked sun-dried tomatoes, and 1/2 cup of crumbled feta cheese on top. The warmth of the orzo will slightly wilt the spinach.

Drizzle the prepared vinaigrette evenly over the salad ingredients. Gently toss the salad using tongs or a large spoon, ensuring that the spinach is lightly wilted and the feta is distributed evenly.