Authentic Filipino Flan

My aunt gave me this Flan recipe many years ago. I LOVE FLAN. It's my all time favorite dessert!

10 egg yolks
14 oz sweetened condensed milk
12 oz evaporated milk
3 TBS margarine
3 TBS brown sugar
1) Whisk together yolks and both milks
2) Melt margarine in saucepan, med. heat
3) Stir in brown sugar. Stir until smooth. Spread mixture over bottom of 9 inch pie plate, let cool for a few minutes* then pour in egg mixture and Spread it over the bottom
4) Cover with foil. Steam for 65-70 minutes. Cool for at least 30 minutes. I put it in the fridge to cool faster!
*I added this because I just remembered that if you don't let the mixture cool, it will cook the eggs!