Preheat oven to 350°F. Line a baking sheet with parchment paper.
In a large bowl, whisk together oil, sugars, egg, vanilla, and water.
¾ cup vegetable oil, 1 cup brown sugar, ½ cup granulated sugar, 1 large egg, 1 teaspoon vanilla extract, ¼ cup water
Sift the flour, salt, and baking soda into the wet ingredients, and then mix by hand with a rubber spatula.
1 cup all-purpose flour, 1 teaspoon salt, 1 teaspoon baking soda
Stir in oats and raisins.
3 cups quick oats, 1 cup raisins
Drop by tablespoon or with a cookie scoop onto the prepared baking sheet.
Bake for 12–15 minutes until golden brown and the edges are set.
Remove from the baking sheet and cool. Transfer to a cooling rack before storing.