Combine the pitted and halved cherries, 3.5 oz sugar, lemon juice, water, and 2 oz maraschino liqueur in a medium saucepan. Bring to a gentle simmer over medium heat and cook for 5 minutes, allowing the cherries to soften and release their juices while the flavors meld together. Remove from heat and let the mixture cool completely to room temperature—this is crucial for both food safety and flavor, as a warm compote will cause the delicate mascarpone cream to break when combined. I like to cool this while I prep the other components, so nothing sits idle.
In a large heatproof bowl, whisk together the 6 egg yolks and 1/2 lb sugar until the mixture becomes pale, thick, and forms ribbons when the whisk is lifted—this takes about 3-5 minutes of vigorous whisking. Gently fold the room-temperature mascarpone into the yolk mixture using a spatula, being careful not to overmix, which can make the mascarpone grainy. In a separate bowl, beat the egg whites to soft peaks (they should form peaks that curl slightly when the beater is lifted), then carefully fold them into the mascarpone mixture in two additions, maintaining as much airiness as possible. Stir in the vanilla extract. I find that folding the whites in two batches rather than all at once helps maintain the volume and creates a lighter, fluffier cream.
In a shallow bowl, combine the 1 cup cooled cherry syrup with 0.6 cup maraschino liqueur, stirring gently to blend. This mixture will be used to soak the ladyfingers, infusing them with cherry and maraschino flavor while keeping them just moist enough to absorb liquid without becoming mushy.
In a 9x13 inch baking dish (or similar size), begin assembly by quickly dipping each ladyfinger into the cherry-maraschino syrup for just 1-2 seconds per side—they should be moistened but not saturated, as they'll continue to absorb liquid as the dessert sits. Arrange a single layer of dipped ladyfingers on the bottom of the dish. Spread a third of the mascarpone cream mixture evenly over the ladyfingers, then distribute a third of the cooled cherry compote over the cream. Repeat this layering two more times: dipped ladyfingers, then mascarpone cream, then cherries, ending with a final layer of mascarpone cream on top. This creates an elegant presentation and ensures each spoonful has the right balance of flavors.
Cover the assembled tiramisu with plastic wrap and refrigerate for at least 2 hours (or up to overnight for best flavor development). The cold time allows the flavors to meld together, the ladyfingers to fully absorb the syrup, and the cream to set to the perfect creamy-but-structured consistency.
Remove the tiramisu from the refrigerator and top with the 8-10 fresh cherries arranged decoratively over the surface. Drizzle any remaining cherry syrup and compote over the top for visual appeal and extra flavor. Serve chilled, using a sharp knife dipped in hot water and wiped clean between cuts to get clean, neat portions.