Place the potatoes and 1 tablespoon kosher salt in a large stockpot and cover with water. Bring to a boil over medium-high heat and cook until the potatoes are tender, 10 minutes. Drain and let cool slightly.
Cut the potatoes into quarters and put them in an extra-large bowl. Sprinkle with the red pepper flakes, celery seeds, 1/2 teaspoon seasoning salt and 1/4 teaspoon black pepper; toss gently until evenly coated. Mix in the hard-boiled eggs.
In a separate bowl, mix together the mayonnaise, onions, peppers, celery, mustard, relish and jalapenos. Mix the dressing into the potato and egg mixture. Serve chilled or at room temperature.