Bring a pot of water to a boil and carefully add 6 hard-boiled eggs. Once the water returns to a boil, remove from heat, cover, and let sit for 7-8 minutes—this ensures perfectly cooked yolks that are creamy, not chalky. Transfer the eggs to a bowl of cold water and let sit for 2 minutes to stop the cooking process, then peel and set aside.
Separate the yolks from 4 of the cooled eggs and place them in a bowl—keep these whole for now. Dice the remaining 2 whole eggs into 1/2-inch pieces and finely chop the 4 egg whites into 1/4-inch pieces. Keep the diced whole eggs and chopped whites separate; you'll need them at different points in the recipe.
In the bowl with the 4 egg yolks, add 2 tablespoons of cottage cheese, mayonnaise, and Dijon mustard. Mash everything together until completely smooth and creamy—this creates the flavor-packed base that will bind the entire salad. I like to use a fork and really work it until there are no lumps; this ensures even distribution of the mustard's tang throughout the salad.
In a large bowl, add the remaining 6 2/3 cups of cottage cheese as your base. Pour in the creamy yolk mixture from Step 3, then fold in the diced whole eggs and chopped egg whites. Add the scallions and season with salt and black pepper, folding gently until everything is evenly combined. I always taste at this point and adjust the seasoning—sometimes I add another pinch of salt if the cottage cheese is particularly mild.
Transfer the egg salad to a serving bowl and top with red pepper flakes for a subtle heat and visual appeal. Serve immediately or chill until ready to serve.