If preparing this salad ahead of time, add all the ingredients to the vinaigrette with the exception of the spinach, then add the spinach on top and let stand until ready to toss.
Whisk together oil and vinegar in a large bowl. Season with salt and pepper. Add spinach, strawberries, almonds, sesame seeds, and feta. Gently toss until spinach is evenly coated with dressing. Serve immediately.