Entree salads are extra appealing as the weather gets warmer. Even though this salad is light and fresh, barley and sauteed chicken give it enough substance to stand on its own. Smarts: Any grain will work here, so feel free to sub quinoa or farro for the barley.
Barley - (Skip if barley was made ahead for Tuesday.) Bring a saucepan of water to boil. Salt water generously and add barley. Cook for 45 to 55 minutes, until tender but not soggy. (Can be done up to 5 days ahead)
Make vinaigrette - If prepping right before cooking, get oven heating before continuing with prep. Whisk together mustard, honey, and vinegar. Add first portion of olive oil while whisking. (Can be done up to 5 days ahead)
Celery - Slice celery. (Can be done up to 4 days ahead)
Bread / Tomatoes - Prep as directed. Store separately. (Can be done up to 2 days ahead)
Spread bread cubes out on a sheet pan. Drizzle with second portion of olive oil and season with some salt and pepper.
Toast until bread is golden and crisp, shaking pan halfway through cooking, 8 to 10 minutes.
Heat a skillet over medium-high heat. Add cooking oil and then chicken to heated oil. Sear chicken on all sides until nearly cooked through, 6 to 8 minutes. In the last minute of cooking add 1 Tbsp / 15 mL of vinaigrette (for 4 servings; adjust if customizing) and continue to cook until vinaigrette coats chicken.
If you’d like the barley warm, reheat in the microwave (you can also serve it at room temperature).
Assemble salad by topping spinach with barley, celery, tomatoes, croutons, and chicken. Add vinaigrette until dressed to your liking. Enjoy!