No Bake Silky Key Lime & Rum Tiramisu

If you are looking for a Key Lime dessert that isn’t key lime pie- look no further. Take the flavors of a key lime pie and turn it into the silkiest tiramisu: layers of tart custard, rum soaked lady fingers and sweet mascarpone cream.

Key Lime Pie is easily my favorite dessert. I will pass on chocolate any day over Key Lime pie. My native Florida roots are showing. For this recipe, I wanted several things- a no bake/ make ahead dessert, key limes, but light, tart, sour and sweet. Yikes! That’s a big bill to fill. I started thinking about my favorite kinds of desserts and tiramisu kept popping into my mind. So I deconstructed a tiramisu and added Key Lime Pie components to come up with this amazing dessert. Instead of an espresso soaked lady finger, I made a simple syrup with rum, ginger, water and sugar.

Rum soaked biscotti, creamy mascapone and limes!

I whipped cream and mascarpone for one layer, make a traditional key lime custard for another layer and topped the whole thing with whipped cream and a dusting of powdered sugar. Definitely give it a try. It is so good, your guests will ask for seconds. Enjoy!

Key lime Tiramisu- serves 4-6

  • 1 cup of fresh key lime juice ( approx. 1 lb of limes)

  • 2 pasteurized egg yolks

  • 28 oz. ( 2 small cans) sweetened condesned milk

  • For the mascarpone cream
  • 8 oz Mascarpone, room temperature

  • 1 cup heavy whipped cream

  • For the Rum Simple Syrup
  • 1 cup light rum

  • 1 cup water

  • 1 cup sugar

  • 1- 1″ piece of ginger, peeled

  • 1 tsp lime zest

  • 1- 7 oz package crunchy lady fingers cookies

  • 1 cup heavy whipping cream, whipped

  • 1 TBSP sugar

  • 1 lime & zest for garnish

  • Powdered sugar for dusting

I highly recommend using a juicer and not hand squeezing these little guys.

Method- Prep time- 1 hour, Make overnight

  • In a medium bowl, combine the key lime juice, sweetened condensed milk and pasteurized eggs yolks. Cover and chill for 1 hour until thick and firm.
  • In the bowl of a stand mixer, whip 1 cup of heavy cream until soft peaks form, whisk in the mascarpone until light and well combined. Cover and chill.
  • In a small saucepan, bring to a simmer the water, sugar, 1 tsp of lime zest and ginger. Off heat add rum. Return to the stove and let simmer until sugar is dissolved. Let cool. Pour into a shallow dish. Remove ginger.
  • Whip remaining heavy cream and add 1 TBSP of sugar until sugar dissolves. Keep chilled until time to assemble the tiramisu.
  • To Assemble:
    Take each cookie and gently dip it in the simple syrup for just a moment. Place in the bottom of an 8 x 8″ dish. You may need to break a few of the cookies to make them fit in a single layer.
  • With an offset spatula, spread the mascarpone cream mixture over the top of the rum-simple syrup soaked biscotti.
  • Add another layer of rum-simple syrup cookie on top of the mascarpone cream. Top with the Key Lime custard.
  • For the topping, spoon 1 cup of the sweetened whipped cream over the top.
    Cover and chill 8 hours or overnight.
    To serve:
    Dust with powdered sugar and sprinkle with lime zest. To serve, cut into squares and top each slice with a thinly sliced lime wedge.
For the custard: one cup of key lime juice, 2 fresh egg yolks and 28oz of sweetened condensed milk
No Baking!
Tart, sweet, sour light- yummy!
Try and eat just one serving.


  1. Susan Ameling

    Looks delicious, can’t wait to try it! Would love to follow your page.

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