Why Won't My Condensed Milk Fudge Set? Common Mistakes & Easy Fixes

If you've ever tried a quick and easy chocolate condensed milk fudge recipe only to find it won't set properly, you're not alone, and I'm here to help! There are a few common reasons fudge doesn't set, and the good news is they're usually pretty easy to rectify.

pile of rocky road fudge on a white plate

Over Christmas, I shared a few fudge recipe videos and noticed a few people on each video asking why their fudge hadn't set. Instead of repeating the same advice over and over in the comments, I thought it would be more useful to put all my tips together in one post.

In this post, I'll go through the most common mistakes and share my top tips for getting perfectly firm fudge slices every time. Just to be clear, I'm talking specifically about chocolate condensed milk fudge here. Traditional fudge, which is made by boiling the mixture to the soft-ball stage, is a different process, so these tips won't apply to those types of recipes.

Mistake 1: Using evaporated milk

A mistake I've seen again and again is beginners using evaporated milk instead of condensed milk. They're usually next to each other in the supermarket and while they may look similar in the tin, they behave very differently.

Evaporated milk is unsweetened milk with most of the water removed. It has a thin, runny texture and is better to use as a low-fat cream substitute. Condensed milk, on the other hand, is evaporated milk with lots of sugar added. It has a thicker texture that is similar to syrup. This is what you need to use when making fudge!

Mistake 2: Boiling the mixture

Traditional fudge requires you to boil the mixture to reach the soft-ball stage. To make chocolate condensed milk fudge, you only need to melt the chocolate. Melt it over low heat and stir gently as you go. Boiling it can cause the fats to split and become greasy, which will prevent it from setting properly. If it's your first time making this type of fudge, you can melt the chocolate on its own first then stir the condensed milk into it.

white chocolate fudge in saucepan — *this is what your mixture should look like before putting it in the tin- nice and thick!*

Mistake 3: Not letting it chill long enough

As different types of chocolate have different additives, you may need to chill your fudge for longer than the recipe states. In my experience, cheaper chocolate bars set much faster than luxury ones due to the added emulsifiers.

White chocolate fudge will take a bit longer than milk chocolate fudge to set, while dark chocolate fudge will set the quickest. 4-6 hours in the fridge should be enough time, regardless of the type of chocolate you've used. If it hasn't set after this time, then something else has probably gone wrong.

Mistake 4: Using chocolate chips

Chocolate chips are usually made to set softer than chocolate bars, which is why they're so good for adding to things like cookies. However, using chocolate bars will help to ensure your fudge sets firmly. Some of my favourite chocolate bars to use for fudge are Ms Molly's from Tesco and Stamford Street Co. from Sainsbury's.

Mistake 5: Using 'light' products

Similarly to using evaporated milk instead of condensed milk, using 'light' condensed milk or sugar-free chocolate can prevent your fudge from setting properly. We need the fat and sugar content in order to create that firm, sliceable texture!

Mistake 6: Incorrect ingredient ratios

If you're using too much condensed milk and not enough chocolate, your fudge won't set. Again, it is dependent on the brand of chocolate you're using, but 400-450g of chocolate with 1 tin of condensed milk (397g/14oz) is a ratio that has consistently worked for me with many different brands. I use 400g of milk or dark chocolate and 450g of white chocolate.

Fudge will set nicely with up to 600g of chocolate per tin of condensed milk, so if your fudge isn't firming up properly, try adding some more chocolate next time.

Mistake 7: Using too much food colouring

Adding too much food colouring (especially the liquid ones) to the fudge can cause it to become too diluted and not set. This can also apply to some flavourings such as alcohol (rum and raisin fudge for example). Stick to powder or gel colours for best results, and measure carefully when adding flavours.

Tips for getting condensed milk fudge to set

For beginners, using a double boiler can help create that thick texture fudge needs to set. Add your ingredients to a heatproof bowl and set it over a saucepan of gently simmering water, ensuring the base of the bowl is not touching the water. Keep the heat low and stir gently until the chocolate has melted. The mixture should look thick and glossy.
Use the cheapest chocolate bars you can find! These will make your fudge set much better than luxury bars or chocolate chips.
Melt the ingredients slowly over very low heat. No need to boil!
Check your ingredients. Make sure you're using condensed milk and not evaporated milk. Avoid low-fat or reduced sugar products.
If you're using food colouring, add powder or gel rather than liquid.

green mint aero fudge overhead thumbnail image

chocolate smartie fudge pieces piled on a plate

Easy fudge recipes to try

I hope you find this post helpful on your chocolate fudge-making journey! If you have any other tips to add, leave a comment below to let me know.