Put the two batches of powdered gelatin each, in 30 ml of water and leave to absorb the moisture (Divide into two for the Bavarian cream and the jelly respectively in 2 heatproof containers.)
Put a bowl underneath a sieve. Cut the watermelon up, and rub against the sieve to extract 650ml of juice. (If you do it this way, only the juice and fruit pulp will fall through to the bowl.)
○Make the Bavarian cream. Beat the egg yolk in a bowl with a whisk. Add 250 ml of watermelon juice little by little and mix well. Add sugar and mix again.
Heat the gelatin from step 1 in the microwave to dissolve (see Hints). Add to the step 3 bowl and mix well. Cool the bowl in ice water, and mix gently with a whisk until creamy. Add softly whipped cream and mix together.
Divide the cream mixture into 4 glasses. Tilt the glasses and chill in the refrigerator until set. (If you line a poundcake tin with a kitchen towel and place the glasses, they'll stay put.)
Make the watermelon jelly. Put the remaining 400 ml of watermelon juice in a bowl, add lemon juice and sugar, and mix together. Dissolve the remaining gelatin in water by microwaving, add to the bowl and mix well.
Pour in the watermelon jelly so that it comes up to the same height as the Bavarian cream, and chill to set in the refrigerator. Garnish with a mint leaves, and it's done.
Story Behind this Recipe
I wanted to come up with a cold dessert using watermelon. I love both Bavarian cream and gelatin desserts, so I combined them in one glass to enjoy them both.
Dissolve the gelatin by microwaving for about 20 seconds. If you heat it too much, the gelatin won't set, so be careful. In step 4, stir the base mix until it's the same consistency as the soft whipped cream before combining the two. (Softly whipped means that it feels a bit thick.) Add the jelly after the Bavarian cream has set. I used powdered sugar since it dissolves easily, but you can use regular sugar too. If the sugar doesn't dissolve easily, warm up the juice a bit.