Store-bought everything bagel topping will absolutely work; however, some brands are extremely heavy on the salt and should be avoided for this recipe. It's super easy to make your own everything bagel topping though: Simply combine equal parts dried minced garlic, dried minced onion, poppy seeds and sesame seeds, then add a pinch of kosher salt. You can also add a few pinches of caraway seeds and/or black sesame seeds if you'd like!