Whisk egg yolks and 4 tbsp sugar together in a mixing bowl. When the color turns clear, add mascarpone cheese and stir until consistency is smooth.
Remove skin from pineapple with a large knife. Cut in half and remove core. Cut a 1 inch slice from the bottom. Place in a food processor with 2 tbsp sugar. Pulse until fruit is finely chopped and has released juice. Drain contents into a strainer and preserve juice. Discard chopped pineapple in strainer. Cut remaining pineapple into 1 inch slices.
Roll 10 ladyfingers in pineapple juice. Do not allow them to sit in the liquid. Ladyfingers should be still firm. Place a layer of lady fingers in a round mold. Cover lady fingers with slices of pineapple. Spoon 1 tsp of juice over pineapple layer. Add a thick layer of mascarpone cream. Repeat process.
Garnish by alternating ladyfingers, remaining pineapple slices, sliced strawberries and wild berries across the top of the tiramisu. Refrigerate for a minimum of 1 hour before serving.