You can replace if you prefer, like Jeremy, Chantilly cream by a meringue French or Italian, so in that case brown the top like in a pear and lime meringue pie.
Remarks
This recipe is very well known in the USA and is typical of the South. There are many different variations: with meringue topping instead of cream, crushed biscuits and butter instead of pastry, etc.
You can find mediocre versions all over Florida. These are ususally over-sweet, artificially flavoured and green coloured. Now, a good Key lime pie is not green!