Preheat oven to 180ºC (350ºF).
Line a baking tray and sides with baking paper.
Brush a muffin pan (12 holes) with 1 tbsp melted butter.
Dust the base and sides of the muffin pan with cocoa, turn over and shake excess off.
Using a medium mixing bowl, place the brownie mix, eggs, ⅓ cup water, and remaining melted butter.
Divide the mixture among the prepared muffin holes.
Place 1 Lindor ball into the center of each hole pushing the ball a third of the way into the mixture.
Bake for 15 minutes until the cake is firm to touch and chocolate Lindor balls have melted.
Let it cool for 2 minutes in the muffin pan, before turning the muffin tray out. Tap the muffin pan to release cakes.
Transfer the cake to serving plates, dust with extra cocoa, dollop with cream, and serve immediately.