Ingredients :

• Sweetened condensed milk — This is what makes the toffee. Use about half a can. Don’t buy unsweetened evaporated milk by mistake — the result really wouldn’t be the same. The brand doesn’t matter; Nestlé or store brands work just as well.
• Salted butter — It’s everywhere in this recipe: in the crust and in the toffee. The salt balances the sugar without you even noticing. If you only have unsalted butter, add a good pinch of sea salt to the toffee when incorporating the condensed milk.
• Shortbread or digestive biscuits — The original recipe uses graham crackers, which aren’t always easy to find in France. Shortbread, light speculoos, or digestive biscuits work very well. Avoid biscuits that are too fatty — the crust would become compact and difficult to cut.
• Very ripe bananas — They should have black spots on the skin. A banana that is still yellow and firm will be bland and slightly astringent. If yours aren’t ripe enough, wait a day or two. They provide the natural sweetness that balances the toffee.