Preheat oven to 350 degrees F. Grease and dust a 9x13 inch pan with flour.
In a large bowl, cream butter and sugar until light and fluffy. Add in eggs, vanilla extract, vinegar,,red food coloring, cocoa powder, salt, and baking soda.
Alternate adding buttermilk and flour a little at a time until just combined. Do not over mix.
Evenly spread batter into prepared ban. Bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.
Immediately, poke holes all over top of cake using the handle of a wooden spoon. Pour sweetened condensed milk over cake. Cool completely.
For the Cream Cheese Frosting
Beat cream cheese until light and fluffy. Stir in salt and vanilla. Gradually add powdered sugar a little at a time. Alternate with milk as needed until you reach your desired consistency.
Spread over cake. Top with sprinkles, and mini chocolate chips if desired.