Edible Geode Crystal (Rock Candy / Sugar) Cake Tutorial

By Jackie

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Printed From https://www.cakecentral.com/tutorial/61781/geode-rock-candy-sugar-cake-edible 2026-02-03

How to make rock candy edible geodes. Ann Reardon of How To Cook That shows us how to make her incredible sugar geodes.

How to make rock candy edible geodes. This rock candy recipe that I developed for geodes is fairly easy to make and they are a pretty addition to any cake or just as a gift on their own.

Fondant Shell

350g (12.35 ounces) fondant

black and brown coloring

Using aluminum foil make a bowl into a rock shape and line with another sheet of aluminium foil.

Marble some grey, black and brown shades of fondant as shown in the video and roll it out.

Roll out some white fondant and place over the top of the coloured fondant.

Place the fondant (rock colour down) over the aluminium foil bowl. You can leave this to dry out or use immediately.

Supersaturated Sugar Solution Recipe

3 cups or 640g (22.58 ounces) sugar
1 cup or 230ml water
few drops of food coloring
few drops flavoring

Heat the sugar and water in the saucepan and stir until completely dissolved. Remove from the heat.
Allow supersaturated sugar solution to cool slightly and then pour into the fondant shell. Leave overnight for crystals to form.
Remove any excess crystals that have formed in the middle, turn upside down and leave to dry out.
Using a sharp knife, trim off excess fondant around the level of the sugar crystals.

Chocolate Shell

300g (10.58 ounces) white chocolate melts or candy melts
2 Tbsp or 14g (0.49 ounces) cocoa powder

Make an alfoil bowl as shown in the video and pour in the hot sugar solution, completely wrap in alfoil and leave for 48 hours for crystals to form. Tip off excess sugar solution, peel off alfoil and leave upside down to drain.
Melt some candy melts or white chocoalte melts and pour over the back of the candy shell. Once set add some cocoa powder to the remaining melts and pour over the top of the white chocolate. Trim to the edges of the crystals.

Video & Recipes By How To Cook That

Recipe: goo.gl/5lkiog Subscribe: bit.ly/H2CThat