Stir pudding powder, sugar and 6 tablespoons of milk until smooth. Bring the remaining milk to the boil in a small pot. Stir the pudding mixture into the boiling milk and let it simmer for about 1 minute. Stir in the egg liqueur.
Take it off the stove.
Debark the toast and cut in half diagonally. Wash the oranges, grate them dry, peel them in zests. Peel oranges so that the white skin is completely removed. Cut the flesh into thin slices.
Line an ovenproof mould (24 x 24 cm Ø) with parchment if necessary. Pour the egg liqueur custard mixture into an ovenproof casserole dish. Press toast triangles into the custard, place a slice of orange between each triangle.
Mix the zests with honey and spread on the casserole. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 12 minutes. Take out and serve. Egg liqueur tastes good with it.