284ml carton double cream, softly whipped, to serve
Cream the butter and sugar in a bowl then add the liqueur and orange zest and spread a little over each pancake. Fold the pancakes into quarters and arrange in a large shallow ovenproof dish. (You can make and chill this up to a day ahead or freeze for up to a month.) Preheat the oven to 190C/gas 5/ fan 170C.
To make the sauce, put the citrus zests, orange juice and sugar in a pan and heat gently until the sugar dissolves. Add 2 tbsp of the liqueur. Bring to the boil then reduce the heat and cook for 7-10 minutes until reduced by half. Set aside. (You can cook, cool and chill this a day ahead.)
Bake the pancakes, covered for 15 minutes. Gently warm the sauce until syrupy then stir in a tbsp of liqueur. Drizzle the pancakes with the sauce and serve with the cream.