Preheat oven to 350°F and prepare two baking sheets with parchment. In a small to medium sized mixing bowl, whisk together the SunButter and the vegetable oil until smooth. Set aside.
Add the eggs, brown sugar, and vanilla to a stand mixer fitted with a whip attachment, then beat until the batter looks fluffy and has almost tripled in volume – about 3-4 minutes on high. Drizzle in the SunButter/oil mixture to the stand mixer, then mix until well combined with the rest of the batter.
In a separate bowl, add the flour, baking powder, and salt, and whisk until well-combined. Then, add the dry ingredients to the stand mixer then beat on medium-low until just combined and smooth. The batter will similar consistency to brownie batter.
Using a small cookie scoop, scoop the batter onto the baking sheets (6 per sheet)
Sprinkle the cookies with a little bit of flaky salt, then bake the cookies for 9 minutes. Allow the cookies to cool completely.
Place 1 scoop of ice cream onto ½ of the cookies, then place the other cookies on top of each half sandwich to make a full ice cream sandwich. Wrap in plastic, then place back into the freezer to set up fully.