Slice the bagels into thin pieces and place on a rimmed half-sheet pan. Pour the oil or melted butter over the sliced bagels and sprinkle with the garlic salt. Toss together to coat the bagels with the oil/butter and salt.
Spread the bagels out in an even layer on the baking sheet and bake on the center rack for 15 minutes. Then remove from the oven and stir the bagel chips. Spread them back out into an even layer and bake for an additional 5 minutes or until crisp all the way through.
Notes
Depending on your oven, you may have to bake yours a bit longer or a minute or so shorter.
Store in an airtight container until ready to use.
Use these in homemade Chex Mix, as croutons on salad or soup, or for dippers/crackers on a cheese board.