While the tart base is cooling, begin making the cheesecake mixture by adding the cream cheese and lime juice into a large microwave safe bowl. Mix on low speed to begin with, then up to medium high until mixture is smooth and evenly mixed.
Next, add the sweetened condensed milk, vanilla extract, and (optional) the food gels. Mix on high speed until well combined.
Pour the mixture into your cooled tart base and chill in the fridge for 2 hours. Garnish with slices of limes and lime zest before serving.
Garnish with slices of limes and lime zest before serving.