Cut 5 thick-cut bacon slices crosswise into 1-inch pieces. Place in a large skillet and cook over medium-low heat until browned and crisp, 8 to 10 minutes.
Meanwhile, prepare the following, adding each to the same large bowl as you complete it: Cut 1 pound broccoli florets into rough 3/4-inch pieces (about 6 cups). Finely chop 1/2 medium red onion (about 2/3 cup). Thinly slice 1 medium scallion.
When the bacon is ready, use a slotted spoon to transfer it to a paper towel-lined plate. Transfer 2 tablespoons of the rendered bacon fat to a medium bowl and discard the remaining fat.
Add 1/2 cup mayonnaise, 1/2 cup plain Greek yogurt, 3 tablespoons rice vinegar, 2 tablespoons granulated sugar, 1 teaspoon kosher salt, and 1/2 teaspoon black pepper to the bacon fat and whisk to combine.
Finely grate the zest of 1 medium lemon over the broccoli (about 1 teaspoon). Juice the lemon over the broccoli (about 3 tablespoons). Add the dressing, half of the cooked bacon, 1/2 cup sliced almonds, and 1 tablespoon toasted white sesame seeds. Toss until well combined.
Garnish with more sesame seeds and the remaining bacon, and serve either at room temperature or chilled.