FOR DRESSING - Add the chopped strawberries, extra virgin olive oil, honey (use maple syrup for vegan), balsamic vinegar, salt, and crushed black pepper into the small jar of a blender.
Blend until smooth. Your dressing is ready.
FOR SALAD - Preheat the oven to 350 degrees F (180 degrees C). Line ½ cup walnuts on a baking tray in a single layer. Toast for 3-4 min until they are crisp, then chop finely.
Transfer 5 0z baby spinach into a large serving bowl.
Top with sliced strawberries, ¼ cup onion slices, 2 oz feta cheese, and chopped toasted walnuts.
Drizzle the dressing on top. Toss the salad well and serve fresh.
I would suggest you make this salad fresh. If you keep it for longer, the baby spinach will not remain fresh and walnuts will lose their crunchiness. You can make the dressing and store it for 2-3 days in the refrigerator.