I have the easiest lime tart recipe;

I buy a tart case or 2.

Then in a bowl, add a can of condensed milk & the juice of 2-3 limes as well as the zest from 2 limes. Mix until it gets thicker (and it does this quickly)

Add the filling to the case(s) and chill until you're ready to serve.

My older kids often make this as it is really so easy and yummy.