Step 1: In a mixing bowl, whisk egg yolks and sugar together until pale and creamy (this takes a few minutes).
Step 2: Add mascarpone cheese and vanilla extract to the yolk mixture. Blend until super smooth, with no lumps.
Step 3: In a separate, very clean bowl, whip the chilled heavy cream until stiff peaks form.
Step 4: Gently fold the whipped cream into the mascarpone mixture until just combined, being careful to keep as much air as possible. Pop this heavenly cream into the fridge.
Step 5: In a small, shallow dish, mix your cooled strong espresso or coffee with 1 tablespoon of sugar until it's completely dissolved.
Step 6: Quickly dip each ladyfinger into the coffee mixture (a swift dunk, not a long soak, or they’ll get mushy).
Step 7: Grab your silicone dome molds (or small, clean bowls) and carefully line the inside of each mold with your coffee-dipped ladyfingers, creating a beautiful shell.
Step 8: Spoon or pipe that luscious mascarpone cream filling into each ladyfinger shell. Fill it up nicely!
Step 9: If your molds are deep enough, you can cover the cream with another dipped ladyfinger, or simply fill the dome completely with cream, leaving a little room for the bottom 'seal.'
Step 10: Transfer your filled domes to the freezer for at least 2 hours, or until they're firm enough to hold their shape.
Step 11: Once firm, carefully unmold your tiramisu domes.
Step 12: Dust generously with unsweetened cocoa powder just before serving. Don't be shy here; it adds so much to the flavor and presentation.
Step 13: If you're feeling extra fancy, garnish with a few whole coffee beans or delicate chocolate shavings.
Step 14: Serve them chilled and watch them disappear!