Heat the oven to 350°F (175°C). Grease a 6-cup jumbo muffin pan and line the bottoms with small parchment rounds.

In a heat-safe bowl, melt the butter and chopped semi-sweet chocolate together in 20-second microwave intervals or over simmering water. Stir until smooth and glossy. Let cool for 5 minutes.

Whisk the sugar into the cooled chocolate mixture. Add the eggs and vanilla, then whisk until the batter is smooth and glossy. Avoid whipping in too much air.

Fold in the flour, cocoa powder, and salt just until no dry streaks remain. Stop mixing once the batter looks even.

Divide the batter evenly among the six prepared molds. Bake for 18 to 22 minutes, until the tops look set and a toothpick inserted near the center comes out with a few moist crumbs.

Let the brownies cool completely in the pan. Run a thin knife around the edges and lift them out carefully. Cool completely on a rack before decorating.

Beat the softened cream cheese and butter until completely smooth. Gradually add the powdered sugar and vanilla, then beat until pale and fluffy. Add heavy cream 1 teaspoon at a time if needed until the frosting is pipeable but still thick.

Transfer the frosting to a piping bag fitted with a large open-star tip. Pipe a thick ruffled beard on each brownie, leaving a small open space in the upper middle for the nose.

Wash and thoroughly dry the strawberries. Remove the green tops to create a flat base. Place one strawberry upside down over the upper portion of each beard, pointed end up. Press gently to seat it.

Place a round candy nose where the strawberry hat meets the frosting beard. Use a small dot of melted white chocolate to hold it in place if needed.

Add a dot of melted white chocolate to the pointed end of each strawberry. Attach a white chocolate truffle or marshmallow and hold briefly until secure.

Dust the finished gnome brownies lightly with powdered sugar, and sprinkle the strawberries with red sanding sugar if using. Chill for 20 minutes before serving.