Preheat the oven and prepare the pan

• Preheat the oven to 170 °C.
• Grease and line a 23 cm cake pan.

Mix the wet ingredients

• In a large bowl, whisk together the eggs, sugar, oil, milk and vanilla until smooth and slightly frothy.

Combine the dry ingredients

• In another bowl, sift together the flour, cocoa powder, baking powder and baking soda.

Combine wet and dry

• Gradually add the dry ingredients to the wet mixture.
• Stir until just combined, without overmixing.

Add the coffee and hot water

• Dissolve the instant coffee in the boiling water.
• Pour it slowly into the batter while stirring; the batter will be thin, which is normal and keeps the cake moist.

Bake the cake

• Pour the batter into the prepared pan.
• Bake until a toothpick inserted in the center comes out clean.

Cool the cake

• Let the cake cool in the pan.

Make the milk chocolate ganache

• Heat the double cream gently in a small saucepan over medium heat until it just begins to simmer, without boiling.
• Remove from the heat and pour the hot cream over the chopped milk chocolate in a heatproof bowl.
• Let it sit so the chocolate softens.

Stir the ganache until smooth

• Stir slowly from the center outward with a whisk or spatula until smooth, glossy and fully combined.
• Let it cool a few minutes before using; the sauce thickens as it cools.

Prepare the feuilletine crunch

• Warm the chocolate spread in the microwave just until soft and spreadable, not hot.
• Add it to the feuilletine and mix gently until fully and evenly coated.

Assemble and chill

• Pour the chocolate sauce over the cooled cake.
• Spread the crunch layer on top.
• Chill before serving.