Prepare a bit of boiling water in a microwave or an electronic kettle on the side (you only need 1 tbsp).

Melt your granulated sugar and water together and heat it in a pot on medium heat.

Don't touch your pot until all of the sugar is melted and starts bubbling. If your sugar mixture starts to brown slightly around the edges, lift up your pot and move it in a circular motion to get the mixture evened out. As your caramel mixture deepens in color, continue to lift up the pot and move it in a circular motion to make sure your caramel coloring is even throughout.

Once your caramel is a deep amber color, CAREFULLY add in your boiling water (USE A NET OR STEP AWAY FROM THE PAN AS MUCH AS YOU CAN BECAUSE THIS WILL CRACKLE AND BOIL!!)

Mix together the caramel mixture and pour it into your 15cm cake pan. QUICKLY spread your caramel layer across the bottom of the pan evenly before it hardens! Let that cool while you prepare your purin and cake batter.

Preheat your oven to 170C or 335F (if your oven takes a long time to preheat, you may have to start preheating your oven before you start making the caramel layer).

In a clean pot, add the milk, vanilla and half of the sugar mixture and heat on low for a few minutes just until you see it start to gently steam (don’t overheat this milk mixture or else you will get a skin on top!) Turn off the heat once your milk mixture is warm.

In a large bowl, GENTLY mix together the 2 full eggs, 4 egg yolks and the other half of the sugar with a whisk.

Add the milk mixture into the egg mixture 1/4 at a time and quickly (BUT GENTLY) mix together to prevent the milk from cooking the eggs. Set aside this purin mixture while you prepare your cake layer.

Begin heating a pot of water to use for your water bath later (when baking the cake).

To make the cake batter, mix together the egg and sugar and whip it up with an electronic mixer (or a stand mixer) until you get a pastel colored fluffy egg mixture.

Sift in the cake flour and gently fold it into your egg mixture with a spatula just until the flour mixture is about to be fully incorporated.

Drizzle in the neutral oil and gently fold it into the batter just until it is evenly mixed — don’t overmix!

To assemble the cake, pour the purin mixture through a sieve over the caramel layer. Then pour the cake layer on top of the purin layer gently — this cake batter is very fluffy which is why it will float on top of the purin mixture!

Prepare your water bath by pouring hot water in a shallow pan and place your cake pan in the shallow water with a paper towel underneath (cover the bottom of your cake pan with aluminum foil if you are worried about water getting into your cake pan)

Bake your cake for 50 to 55 minutes until the top of your cake is golden brown — if your oven is strong, it may bake the top too quickly and you may need to cover your cake in aluminum foil so keep an eye on it for the last 5-10 minutes!

Remove your cake gently from the water bath once it’s done baking and let it cool on a heat-safe surface for at least 30 minutes at room temperature or until it is safe to touch and place in the fridge overnight. If you want to speed up the process, you can place it in a shallow ice bath until it is ready to be placed in the fridge.

Once your cake has rested in the fridge for at least 10 hours or overnight if possible, it’s ready to eat!

電気ケトルで沸騰したお湯を用意しておきます、量は大さじ１あれば十分です。

グラニュー糖と水を鍋に入れ、中火で加熱しながら一緒に溶かします。

鍋の中の砂糖が完全に溶けて泡立ち始めるまで触らないでください。もし砂糖が溶けてから周りが少し茶色くなり始めたら、鍋を持ち上げ、円を描くように動かして色を均一にします。カラメルの色が深くなるにつれて、鍋を持ち上げて円を描くように動かし、カラメルの色を均一にします。

カラメルが濃い琥珀色になったら、注意深く沸騰したお湯を加えます（ネットを使うか、鍋からできるだけ離れてください！この際に跳ねて沸騰するので非常に注意が必要です！）

カラメルを混ぜ合わせたら、15cmのケーキ型に流し込みます。固まる前に素早くカラメル層を型の底に均一に広げます。プリン液とケーキ生地を準備している間、冷ましておきます。

オーブンを170℃または335°Fに予熱します（オーブンの予熱に時間がかかる場合は、カラメル層を作る前に予熱を始めてください）。

綺麗な鍋に牛乳、バニラ、砂糖の半量を入れ、弱火で数分間加熱します。表面が軽く蒸気を立てるくらいまで温めます（加熱しすぎると表面に膜ができてしまうので注意！）温かくなったら火を止めます。

大きなボウルに全卵2個、卵黄4個、残りの砂糖を泡立て器で優しく混ぜます。

牛乳の混合物を卵液に1/4ずつ加え、その都度素早く（でも優しく）混ぜて、牛乳が卵を調理しないようにします。このプリン液を置いておき、次にケーキ生地を準備します。

後で使う湯煎用のお湯を鍋で加熱し始めます。

ケーキ生地を作るために、卵と砂糖を混ぜ、泡立て器（またはスタンドミキサー）で淡い色のふんわりとした状態になるまで泡立てます。

薄力粉をふるいにかけて加え、ゴムベラで優しく折り込むように混ぜます。

サラダ油を少しずつ加え、生地が均一になるまで優しく混ぜます（混ぜすぎないよう注意）。

浅い耐熱皿に熱湯を注ぎ、ケーキ型をその中に置きます（ケーキ型の底にアルミホイルを巻いて、水が入らないようにすると良いです）。

焼き上がったケーキを湯煎から取り出し、耐熱の台に置いて少なくとも30分間常温で冷まします。その後、冷蔵庫に入れる前に浅い氷水で冷やしても良いです。ケーキを一晩冷蔵庫で冷やすか、少なくとも10時間冷やしてください。

ケーキが十分冷えたら、大きなお皿をケーキ型の上に置き、素早くひっくり返します。ケーキは柔らかいので素早く行ってください。ケーキ型を優しく持ち上げると、カラメルが滴り落ちてケーキに染み込む様子が見られます。