Preheat oven to 325F.
Place cherry tomatoes in a medium oven safe baking dish, and pour olive oil and oil making sure tomatoes are fully submerged. Put the garlic salt and herbs around the tomatoes evenly. Bake in the oven for 40 minutes then remove and let cool.
Using a slotted spoon, transfer the tomatoes, garlic and herbs into and air tight container. Pour the cooking oil on top, seal and refrigerate for up to two weeks.