Key Lime Pie – we all know what that is. Key Lime Bars are obviously the tray bake version. But we can’t get Key Limes in the UK. So I’m just doing Lime Bars. When I was asked what I’m baking this weekend I said ‘lime bars’ and got blank stares from some people, and a mistaken excited ‘oh I love Dime Bars’…

According to ATK normal limes are Persian Limes, so I’m calling my lime bars Persian Lime Bars in an attempt to remove the confusion, with the side benefit of making them sound more exotic :)

I’m using the recipe for Key Lime Bars from ATK’s Family Baking book (p223). They have a makeover version in their Comfort Food Makeover book, but it’s just ‘use low-fat versions of cream cheese and condensed milk’, so it’s not much of a makeover, and certainly not a very interesting one, so I’m just going with the standard recipe. Plus I’m making these for work, so most of the calories will go to my work colleagues, not us :P

The recipe calls for the biscuit base to be made with Animal Crackers, but we can only get the milk-chocolate covered ones in the UK, so I’m going with the staple digestives for the base. So the crust is made with:

• 5 ounces of digestive biscuits
• 3 tbsp light brown sugar
• 1/8 tsp salt
• 60g unsalted butter, melted

The digestives go in the food processor with the sugar and salt and get turned into crumbs, then the melted butter is poured over and pulsed into the biscuit mix. This gets pressed into an 8″ square baking tray that’s been lined with a foil sling. One benefit of succumbing to buying some proper US-style measuring cups is that I can use them to press down the base, as the recipe recommends :)

The base then goes in a 140c fan oven for 20 minutes, turning half way through.

For the filling:

• 2 oz cream cheese
• 1 tbsp grated (Persian :) lime zest
• 400g sweetened condensed milk
• 1 egg yolk
• 1/2 cup freshly squeezed (Persian :) lime juice

Basically this is all whisked together, then poured over the based. Then it gets baked, at 140c fan again, for 15-20 minutes (turning half ay through) until the bars set and pull away from the edges of the tray.

This cools on a rack for 2 hours, then it gets covered in foil and goes in the fridge for 2 hours. Only then does it come out of the tin (using the foil sling) to be cut into squares, and finally the squares are topped with a sprinkle of toasted desiccated coconut.

After testing a square each (yeah they are tangy and tasty :)  we pack them in a plastic box ready for transporting to work in the morning, but keep them in the fridge until I leave. Let’s hope I don’t forget them…