The source combines espresso, sweetened condensed milk and cola for a chilled coffee drink. The components provide concentration, sweetness, dairy texture and carbonation. Their proportions matter more than a claim that any homemade version must outperform every commercial product.
Blend the espresso and condensed milk into an even mixture before combining with the serving ice and cola. This helps distribute the thick sweetener rather than leaving it at the bottom. Add the carbonated component gently and leave sufficient space in the glass for the mixture to rise.
Compare the drink immediately after assembly and as the ice melts. A different cola or a different espresso strength can change both sweetness and balance, so keep a record of the actual ingredients. The result is a recipe direction to adapt thoughtfully, not a BeanScene-tested ranking or a universal statement that more coffee or more condensed milk will improve it.

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