1-Preheat oven to 220°C (fan forced 200°C). Grease and line two baking trays with parchment paper.

2-Boil water and solid fat in a saucepan. Add flour and stir for 3 to 5 minutes until mixture forms a mass that leaves the pan sides. Remove from heat and rest 5 minutes.

3-Beat in eggs one at a time with an electric mixer until mixture is stiff, glossy, and holds shape.

4-Spoon or pipe 18 walnut-sized balls onto trays spaced 6cm apart. Bake 10 minutes at 220°C, rotate trays, reduce heat to 200°C, and bake 10 more minutes until brown and springy to touch. Cool on trays 5-10 minutes, then transfer to wire racks.

5-For custard, bring cream, milk, coffee liqueur, and vanilla paste to boil in a saucepan and remove from heat. Whisk egg yolks, sugar, and corn flour; slowly whisk in the cream mixture. Return to low heat, stirring until custard thickens and coats spoon back. Cool, cover, and refrigerate.

6-Fill a piping bag with custard, make a small hole in bottom of each profiterole, and pipe filling inside.

7-Melt milk chocolate and add pouring cream gradually, mixing smooth. Melt white chocolate separately. Spoon milk chocolate over profiteroles, allow to set, then drizzle white chocolate on top and decorate with edible balls or sprinkles.