Take the cream cheese and butter out of the refrigerator so that they can start to soften. Line two baking sheets with parchment paper. Preheat the oven to 350°F (180°C).
Prepare the egg replacer by mixing it with the plant milk until it's lump-free. Set it aside for now.
Combine the flour, cocoa powder, baking soda, and salt in a medium bowl. Set it aside.
Cream the butter and brown sugar together in a large bowl until the mixture looks light and fluffy. Use a mixer or fork for this.
Add the egg replacer, vanilla, red color, and white vinegar to the large bowl. Beat or stir them in until they're fully combined. Check the red color to see if you want to add more at this point.
Add the flour mixture to the large bowl. Gently fold the ingredients together until all of the dry bits are incorporated into the cookie dough.
Roll the dough into 1.5 tbsp balls. Place them about 2 inches apart. Bake them for 9-11 minutes until the edges look stiff, but the centers are still soft and puffy. Try not to over-bake them because they will continue to set once they're out of the oven.
Tap the cookie sheet onto the counter to help the cookies flatten, or press them down a bit with a spoon if you want a flatter cookie. Let them cool for at least 10 minutes.
Meanwhile, make the frosting. Mix the butter and cream cheese together with a mixer. Then mix in the powdered sugar a little at a time. Place it in the refrigerator to chill while you wait for the cookies to cool down.
Frost the cookies and enjoy! You can also decorate them with a few crushed cookie crumbs.