In a medium-sized bowl cream together the peanut butter, vegan cream cheese, sugars, vanilla, and milk until light and fluffy, approximately two minutes.
In a separate bowl, combine the flour, flaxseeds, cornstarch, baking soda, baking powder, and sea salt. Stir until well combined and then pour into wet ingredients.
Stir until the dough forms a ball. Cover the dough with a lid or plastic wrap and refrigerate for 30 minutes to an hour. (You can even make this ahead and let the dough chill until the next day).
When you're ready to bake the cookies, heat your oven to 350˚F.
Use a cookie dough dispenser or a large spoon to drop dough onto a cookie sheet, allowing 2 inches between. Use a fork to make a criss-cross pattern in the tops of each cookie dough ball.
Bake for 10 - 12 minutes. The centers should still be soft, but the edges will be a nice golden color. Once they're cool enough to handle, place on a wire wrack to cool.
Store cookies in an airtight container at room temperature for up to 3 days, in the fridge for up to 7 days, or in the freezer for up to 2 months.