Crack 6 whole eggs and separate 4 additional egg yolks. Beat the eggs and yolks together until well mixed.

Add the sweetened condensed milk, whole milk, and vanilla extract. Stir until fully combined.

Make the caramel: In a saucepan, combine sugar and a little water. Cook over medium heat until the mixture turns a golden amber color. Add a small amount of diluted coffee, stir well, then pour the caramel into the bottom of your molds.

Once the caramel hardens, pour the egg and milk mixture into the molds. Steam the flan for 20 minutes. To check for doneness, insert a toothpick straight into the flan—if it comes out clean, the flan is done. Turn off the heat, let cool, then refrigerate.
Note: Use medium heat and wipe the lid every 5-7 minutes to prevent condensation from dripping onto the flan.