I will try my best to explain.

Ingredients for Flan

• 3 whole eggs and one egg white
• 1 can of condenced milk
• 1 can of evaporated milk,
• 1 teaspoon of vanilla extract
• 1/2 cup of white chocolate chips,
• Instructions: Blend ingredients until completly smoothe.

Ingredients for Red velvet 

I have tried many different red velvel recepies, even just the boxed red velvel mixes work fine. the recepie i use makes 2, 9 inch cakes because every time i make the red velvet faln i make a red velvet cake as well. 

•  1 cup of vegtable oil
• 2 eggs,
• 1 1/2 cups of sugar
• 1 teaspoon cocoa powder
• 2oz red food coloring
• 2 1/2 cups of flour
• 1 teaspoon of vanilla
• 1 teaspoon of vinegar,
• 1 teaspoon of baking soda

Instructions: Put it all in the cake mixer untill there are no more bumps. (i use a little less than half for the flan) but its preference some people like more flan other more cake.

Caramel

As for the caramel that goes on top i have used many different ones also and everyone seams to like thm all, it can be simply melted sugar, whatever you favorite bottled caramel is, or what i like to use "cajeta" which is kinda like a mexican caramel.  It can be found in just about in any greocery store in california.  I normally get it from Vallarta.

You need a 9 inch cake pan and a 12 inch cake pan, I spray the entire 9 inch pan with baking spray to avoid sticking. Coat the bottom of the pan with a thin layer of caramel/cajeta (try to use a thick caramel/cajeta, something not too watery to avoid it mixing with the cake), then slowly and carefully add the red velvet mixture, i usually fill to about 1/4 of the way up with the red velvet (but again that is just the way i like it) then poar the flan mix in very slowly from just one side so it doesnt completly mix together, dont worry if it sinks to the bottom or mixes together in swirls, it will separate while baking :) Cover tightly with aluminum foil (dont forget to spray the foil so it does not stick at the top). Fill the 12 inch pan about 1/4 with water and put the 9 inch pan right in the middle thenpre heat oven to 350.  Bake for an hour and 45 minutes, remove the aluminum as soon as you take it out but let it sit and cool down for at least an hour before flipping onto a dish.