In a large mixing bowl, cut butter up into pieces and allow to sit at room temperature for 20 minutes.
In a separate bowl, mix eggs, yolks and vanilla until well-combined.
Preheat oven to 325 degrees and make sure rack is placed in middle of oven.
Grease and flour a 9x5 loaf pan.
Using a mixer set to high, beat butter until creamy, about 2-3 minutes.
Continue mixing on medium while slowly adding sugar and mix for 1 minute.
Increase speed to high again and continue to mix until light and fluffy, about 5 minutes.
Reduce speed to medium again and slowly add egg mixture until fully incorporated.
Mix now on high for 3 minutes,
Sift flour over mixture in 3-4 step: while folding flour into batter, using spatula until all flour is folded in.
Pour mix into prepared pan and smooth top.
Bake until golden brown and toothpick comes out clean, about an hour and 10 minutes.
Remove from oven and allow to cool on wire rack for 15 minutes before removing from pan.
Allow to cool completely for at least 1 hour and 30 minutes.
To prepare topping:
In a medium-sized bowl, add sparkling wine and sugar and mix until all sugar has dissolved.
Add strawberries and refrigerate for at least 30 minutes.
In a medium bowl, add heavy cream and mix with hand mixer for 4-6 minutes until cream forms medium peaks:
To assemble the plate:
Slice cake and lay on plate. Spoon 2 Tbsp of juice from strawberry mixture onto each slice of cake and allow the cake to absorb liquid.
Top with sliced strawberries and whipped cream and garnish with mint leaves.