Preheat oven to 350 degrees. Line two baking sheets with parchment paper.
Combine 1 Tbsp. flaxseed meal with 3 Tbsp. warm water, mixing well. Set aside. This is your "flax egg."
In the bowl of a stand mixer fitted with a paddle attachment, cream the shortening, granulated sugar, and light brown sugar, mixing on medium speed for about 3 minutes. Add the vanilla extract and the flax egg. Mix about 30 seconds on low speed until combined.
In a separate bowl, whisk together flour, the remaining 1/4 cup flaxseed meal, gum, baking soda, baking powder, cinnamon, and salt. Add oats and mix.
Add dry mixture to stand mixer bowl, and mix on low speed until combined. Add raisins and chocolate chips, mixing on lowest possible speed until just combined.
Using a 2-Tbsp. scoop, place dough balls on a baking sheet and flatten them slightly.
Bake in the center of the oven 13 minutes, until lightly golden.
Let cookies cool for about 5 minutes before transferring to a cooling rack.
For a fructose-free version, substitute 1 cup birch sugar (xylitol) for the granulated sugar and light brown sugar. Omit the raisins, and use 1 1/4 cups sugar-free, fructose-free mini chocolate chips. Bake about 16 minutes, and let rest at least 10 minutes before transferring to cooling rack.