This delectable open-faced sandwich requires a slice of toasted rustic whole-grain bread as a crisp foundation. What is rustic bread? It’s not easy to define. Some might describe it as artisanal without any preservatives. It’s sold unsliced, usually in round or oval shapes. The bread has a crusty exterior and an interior with a chewy texture.

Atop the toast a large leaf of red leaf lettuce cradles a scrumptious egg salad concoction. Instead of mayonnaise, plain fat-free yogurt gives the mix an alluring pop of flavor, adding an edge of creamy tartness. Fresh dill and chives add a welcome herbaceous note.

Open-Faced Egg Salad Sandwiches

Yield: 4 servings

5 large eggs

4 slices rustic whole grain bread, about 3/8-inch thick

1 large garlic clove cut in half lengthwise

2 1/2 tablespoons plain, fat-free yogurt, plus more if needed.

2 tablespoons finely chopped fresh dill

Coarse salt and freshly ground pepper to taste

1/2 teaspoon minced lemon zest (colored portion of peel)

Red leaf lettuce or green leaf lettuce

Garnish: chopped chives

1. To hard cook the eggs: Put eggs in small saucepan with water to cover by 1 inch. Place on high heat. When water comes to a boil, cover and remove from heat. Allow eggs to sit covered for 12 minutes. Drain and run cold water over eggs. When cool enough to handle, crack and peel in cold water, place in airtight container and refrigerate.

2. Adjust oven rack to 6-inches below broiler element; preheat broiler. Place bread on rimmed baking sheet and place under broiler. Broil until toasted, about 1 1/2 to 2 minutes; turn on oven light and watch the progress because bread burns easily. Place each piece of toasted bread on a salad plate; rub top of bread with cut-side of garlic.

3. In a medium bowl, combine yogurt, dill, salt, pepper, and zest; stir to combine. Coarsely chop eggs and add to yogurt mixture; stir to combine. Taste and adjust seasoning as needed, adding more yogurt if needed for a creamy consistency.

4. Top each toast with a lettuce leaf or two (or more if you like). Top with egg salad. Sprinkle with chopped chives.

Source: “50 Best Plants on the Planet” by Cathy Thomas (Chronicle, $29.95)