1. Sesame Crunch: Preheat oven to 350 degrees. Combine almonds, sesame seeds, coriander, sugar, 1/4 teaspoon salt, and 1/8 teaspoon pepper in a bowl. Add egg white and stir to combine. Spread mixture into a single layer on a rimmed baking sheet.

2. Roast, stirring once, until golden and crunchy, about 12 minutes. If sticking to pan, scrape up with a spatula, then let cool completely. Crunch can be stored in an airtight container at room temperature up to 1 week. (Makes 3/4 cup.)

3. Salad: Remove peel and white pith from grapefruits. Slice 2 into 1/4-inch-thick rounds. Hold remaining grapefruit over a bowl and cut between membranes, allowing segments to fall into bowl. Squeeze juice into bowl.

4. Whisk together mustard, vinegar, 2 teaspoons juice, and coriander. Gradually whisk in both oils until thick and emulsified. Season with salt and pepper.

5. Toss lettuce with 1/4 cup dressing; season with salt and pepper. Serve with avocados, grapefruit slices and segments, herbs, and sesame crunch, drizzled with more dressing.