Wash the plums or nectarines, dab dry and cut in half. Stone the fruit. Cut the fruit flesh into thin slices
Heat the fat. Add the plums or nectarines and lemon peel and steam for approx. 2 minutes, stirring gently from time to time
add 2-3 tablespoons of sugar and cinnamon to the fruit and toss until the sugar is dissolved
For the advocaat foam, place eggs, 1-2 tbsp. sugar and advocaat in a metal bowl. Whisk everything in a hot water bath with the whisk of the hand mixer for a few minutes until light foamy
Arrange steamed plums or nectarines on four dessert plates. Spread egg liqueur foam over them. Garnish with a few lemon shavings as desired