In small mixing bowl whisk together all of the dressing ingredients until well combined. Or shake the ingredients together in a mason jar with a tight-fitting lid.
Place the spinach in a large serving bowl. Add the strawberries and red onion.
Drizzle about half of the dressing over the salad and toss to coat the leaves. Add more to taste. Add the feta and pecans.
Toss lightly to combine.
Serve immediately, with extra dressing on the side as desired. If you don’t plan to eat all the salad right away, dress only what you will eat and store the rest in an airtight container in the refrigerator. Shake the dressing before serving.
To toast pecans: Spread the pecans in a single layer on an un-greased baking sheet. Bake for 8 to 10 minutes at 350 degrees, until the pecans smell fragrant.
For onions: Place the sliced onions in a bowl and cover with cold water. Let sit while you prepare the rest of the salad (this keeps their flavor but removes the harsh onion bite).