Preparation

• Step 1

  Add the chocolate into a heatproof bowl and set it over a double boiler (a small pot with about 4 inches of simmering water). Mix the chocolate as it melts and stir in the oil until combined well. Immediately remove the bowl from heat once all the chocolate has melted.

• Step 2

  Meanwhile, whisk the egg yolks and ¼ cup sugar into a seperate medium bowl until the mixture is smooth and pale yellow, about 3-5 minutes.

• Step 3

  Pour half of the egg yolk mixture into the melted chocolate and whisk to combine. Add the remaining egg yolk and sugar mixture into the chocolate and whisk until completely combined and smooth. Set aside.

• Step 4

  Place the egg whites into the bowl of a stand mixer fitted with a whisk attachment. Beat on low for 30 seconds and then increase the speed to medium for another 30 seconds. Increase the speed to medium and beat until soft peaks form. Gradually add the remaining ¼ cup of sugar into the egg whites until stiff peaks are formed, being careful not to over beat (about 1 minute longer).

• Step 5

  Gently whisk ⅓ of the beaten egg whites into the chocolate mixture until combined. Gently fold in the remaining egg whites in 2 more equal batches until all the egg whites are folded into the chocolate mousse and there are no white streaks. 

• Step 6

  Pour the rum and water into a small bowl. Dip both sides of one lady finger into the rum and place it into the bottom of an individual serving glass or bowl. Add enough chocolate mousse over the lady finger to fill the verrine. Continue filling the remaining 5 glasses with the remaining chocolate mousse and lady fingers.

• Step 7

  Cover the glasses with plastic wrap and refrigerate for at least 3 hours in the refrigerator or ideally overnight.

• Step 8

  Serve cold for dessert.