Springtime Spinach Salad

Ingredients

• 3 tablespoons red wine vinegar
• Salt and pepper
• 2 tablespoons Dijon mustard
• 2 garlic cloves, minced
• 1/2 teaspoon minced fresh thyme
• 1/4 cup extra-virgin olive oil
• 3 slices hearty white bread, cut into 1/2-inch cubes
• 1 red onion, halved and sliced thin
• 1 teaspoon sugar
• 3 hard-cooked eggs, peeled, yolks and whites separated
• 1 (10-ounce) bag baby spinach