Preheat oven to 325°F (160°C). Place 5 ramekins in a deep baking dish & Set aside.
Heat the 35 % cream & milk in a saucepan over medium heat & whisk constantly the liquids, until it starts to gently boil on the sides.
Meanwhile, whisk egg yolks and a 1/4 cup of sugar until thick and creamy, about 5 minutes. Add in vanilla extract and combine.
Take the hot cream & gradually whisk into the egg yolk mixture. Once all the cream is well incorporated, strain the liquid through fine mesh sieve.
Fill the ramekins with the custard, dividing evenly or up to 3/4 of the way full & place them inside the deep baking dish.
Pour boiling water into the deep baking dish, until the water reach halfway up the ramekins. Try to avoid splashing the water inside the ramekins.
Transfer the baking dish in the oven and bake for 30 to 35 minutes or until it’s set.
Remove carefully ramekins (they will be HOT!) from the baking dish and cool on wire rack or on kitchen towel.
When the ramekins are well cooled down, cover them with plastic food wrap and refrigerate for 2 hours.