Cybele Pascal gives allergen-free replacements for common baking ingredients.
Preheat oven to 350 degrees. Stir together oats, flour, wheat germ, baking soda, baking powder, cinnamon, and salt, in a large bowl.
Put butter and sugars in the bowl of an electric mixer fitted with the paddle attachment. Mix on medium speed until pale and fluffy, about 5 minutes. In a small bowl, whisk together ground flaxseed and water; mix into butter mixture along with vanilla. Reduce speed to low. Add oat mixture; mix until just combined. Mix in raisins.
Using a 1 1/2-inch ice cream scoop, drop dough onto baking sheets lined with parchment paper, spacing 2 inches apart. Flatten slightly.
Bake until golden and just set, about 14 minutes, rotating halfway through. Let cool on sheets on wire racks 5 minutes. Transfer cookies to wire racks; let cool completely. Cookies can be stored in airtight containers at room temperature up to 3 days.