Make the Strawberry Jam/Syrup:

• In a medium saucepan, combine the 1 pound of sliced strawberries, granulated sugar, and lemon juice.
• Cook over medium-high heat, stirring occasionally, until the mixture comes to a boil.
• Reduce the heat to medium-low and simmer, stirring occasionally, until the strawberries break down and the mixture thickens into a jam-like consistency with some syrup (about 10-15 minutes).
• Strain the mixture through a fine-mesh sieve, pressing gently on the solids to extract as much syrup as possible. Reserve both the thick syrup and the strawberry solids separately.
• Refrigerate the strawberry syrup for at least 1-2 hours, or until completely cool.

Make the Mascarpone Filling:

• In a large bowl, combine the room-temperature mascarpone cheese, 1/4 cup of the confectioners’ sugar, lime zest, and vanilla extract. Beat with an electric mixer (hand mixer or stand mixer) on low speed until smooth and combined.
• In a separate, chilled bowl, whip the very cold heavy whipping cream with the remaining 1/4 cup of confectioners’ sugar using an electric mixer on medium-high speed until slightly stiff peaks form (2-3 minutes). Be careful not to overwhip into butter.
• Gently fold the whipped cream into the mascarpone mixture with a spatula until just combined.

Assemble the Strawberry Tiramisu:

• First Layer (Ladyfingers): Briefly dip each ladyfinger cookie into the cooled strawberry syrup (do not oversaturate). Arrange the dipped ladyfingers in a single layer on the bottom of a 13×13-inch square baking pan (or a similar large dish, like a 9×13).
• Second Layer (Mascarpone Cream): Spread half of the mascarpone cream mixture evenly over the ladyfinger layer.
• Third Layer (Strawberries): Arrange a layer of sliced fresh strawberries over the mascarpone cream.
• Fourth Layer (Ladyfingers): Add another layer of ladyfingers dipped in the strawberry syrup.
• Fifth Layer (Mascarpone Cream): Spread the remaining mascarpone cream mixture evenly over the second layer of ladyfingers.
• Sixth Layer (Strawberries): Arrange a final layer of sliced fresh strawberries on top.

Chill: Cover the baking pan tightly with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to meld and the dessert to set properly.  

Serve: Before serving, you can optionally brush the top layer of strawberries with some of the remaining strawberry syrup for extra shine and flavor. Cut into squares and serve chilled.