Ingredients

Caramel Sauce

   
100g granulated sugar
20g water (room temperature)
20g hot water

Custard

   
400g whole milk
100g heavy cream
3g vanilla extract
3 large eggs (50g without shell)
70g granulated sugar

Steps

  1. Preheat oven to 300°F. Boil 3–4 cups water and keep hot.

  2. Make the caramel: combine 100g sugar and room-temperature water in a heavy-bottomed saucepan over medium-low. Let dissolve without stirring. Increase heat to medium. Swirl the pan occasionally — do not use a utensil. When amber and smoking slightly, remove from heat. Carefully add hot water via a spatula (it will sputter). Swirl to combine. Immediately pour into molds.

  3. Heat milk, cream, and vanilla in a saucepan until just before simmering. Remove from heat.

  4. Whisk eggs in a large bowl until smooth. Add 70g sugar and mix. Slowly pour in the hot milk mixture while whisking continuously.

  5. Strain through a fine-mesh sieve into a clean bowl. Divide into molds. Pop surface bubbles with a lighter flame or toothpick.

  6. Place molds in a baking dish. Add hot water halfway up the sides of the molds (bain-marie). Bake at 300°F for 35–45 minutes until set but still jiggly.

  7. Cool completely on a wire rack. Cover and refrigerate at least 2 hours.

  8. To serve: run a knife around the edge, place a plate on top, and flip.

Analysis

Total custard base: 723g (caramel sauce excluded — it’s a separate layer)

Component Amount %
Structure solids — —
Fat (cream, milk, yolk) 51g 7.1%
Sugar (added + lactose) 92g 12.7%
Liquid (milk, cream, egg water) 558g 77.2%
Egg/protein 22g 3.0%

A pure egg-set custard — no flour or starch at all. With zero structure solids, the entire set comes from egg protein coagulating (~3% protein) in a very high-liquid base (~77%). That’s why it’s so delicate and why the gentle bain-marie matters: too much heat and the protein over-coagulates into holes (“su”). The caramel layer (100g sugar) sits separately and isn’t part of these numbers.

Notes

  • Strain the custard — even if you think it’s smooth, there are always lumps.
  • Use a candle lighter to pop surface bubbles before baking. Much faster than a toothpick.
  • The bain-marie is essential for gentle, even heat. Without it you’ll get honeycomb-like holes in the custard (called “su” in Japanese — considered a failure).
  • Thicker ceramic ramekins need longer baking (45–60 minutes). Thin aluminum or stainless steel molds cook faster.
  • Check doneness by tilting the mold — the custard should jiggle but not flow.
  • Don’t overcook. The residual heat will finish setting the custard.
  • Keeps refrigerated 3–4 days in the molds. Unmold just before serving.
  • Stovetop alternative: place molds in a pot of simmering water, cover with a towel-wrapped lid, simmer 10 minutes on low, then turn off heat and let sit covered 10 more minutes.