Whisk the mascarpone cheese and ¼ cup of orange liqueur in a large bowl.
Use a second bowl to whisk the heavy whipping cream with an electric mixer until creamy. Sift in the powdered sugar and continue to beat until peaks begin to form.
Use a spatula to fold the whipped cream into the mascarpone mixture.
Combine ½ cup orange juice and ½ cup orange liqueur in a shallow bowl.
Assembling The Strawberry Tiramisu
Spread half the strawberry preserve on the bottom of a 13x9 baking dish.Lightly dip ladyfinger into the orange liqueur mixture. Add a single layer of ladyfingers on top of the strawberry preserve.
Top the ladyfingers with a layer of sliced strawberries. Spread half of the mascarpone cream filling on top of the strawberries.
Add a second layer of orange liqueur dipped ladyfingers. Top with remaining strawberry preserve. Add a second layer of the mascarpone cream filling. Use a flat knife or cake leveler to spread the mascarpone cream filling evenly. Finish with a second layer of sliced strawberries.
Cover with plastic wrap and chill for a minimum of 8 hours in the fridge. Overnight is even better.