In a small saucepan, heat 1 cup of heavy cream over medium heat until it just begins to simmer. Remove from heat and add the Earl Grey tea leaves. Cover and let steep for 10 minutes.

After steeping, strain the cream through a fine-mesh sieve to remove the tea leaves. Return the cream to the saucepan.

Add the chopped dark chocolate to the infused cream and stir over low heat until the chocolate is completely melted and the mixture is smooth. Remove from heat and let cool slightly.

In a large mixing bowl, whip the remaining cup of heavy cream with the sugar and vanilla extract until soft peaks form. Be careful not to overwhip.

In another clean bowl, whisk the egg whites with a pinch of salt until stiff peaks form.

Gently fold the whipped cream into the cooled chocolate mixture until fully combined.

Next, gently fold in the whipped egg whites, one-third at a time, being careful not to deflate the mixture.

Once combined, spoon the mousse into individual serving glasses or bowls and refrigerate for at least 4 hours or until set.