Strawberry Yogurt Cream:
Line a fine-mesh sieve with a double layer of cheesecloth and place it over a bowl.
Pour the yogurt into the sieve and cover with plastic wrap.
Let drain in the refrigerator for 1 to 2 hours.

Cut half of the strawberries into small cubes. Reserve in a small bowl.
Reduce the other half of the strawberries to a smooth purée with the sugar.
Combine the purée with the reserved strawberry cubes and mix.

Pour the drained yogurt into a bowl. Add the vanilla seeds and mix.
Incorporate the whipped cream, lifting with a whisk.
Add the strawberry mixture without overmixing to preserve a marbled effect.
Refrigerate the preparation for at least 1 hour.

Pâte à Choux:
Preheat the oven to 425 F (220 C).
Line two baking sheets with silicone mats or parchment paper.

In a heavy-bottomed saucepan, bring the water, butter, salt, and sugar to a boil.
When the mixture reaches a boil, pour in the flour all at once and stir vigorously with a wooden spoon for 1 minute, until a ball of dough forms that detaches completely from the bottom of the saucepan.
Pour the ball into the mixer bowl, fitted with the whisk, and add the eggs one by one, whipping quickly.
The pâte à choux should have a smooth consistency, but not be too soft.
Put the dough into a piping bag fitted with a round tip, and deposit small, round balls of dough, about 2″ (5 cm) in diameter, spacing them 2″ (5 cm) apart.
Smooth the tops with a moistened finger.

Bake the puffs for 10 minutes, then reduce the oven temperature to 350 F (180 C) and continue baking for 25 minutes.
Remove from the oven and place the puffs on a rack to cool completely.

Assembly:
Using a sharp knife, cut the puffs 2/3 of the way up from the bottom.
Divide the strawberry yogurt cream among the puffs, then replace the tops.
Cover with plastic wrap and refrigerate until serving time.
At serving time, dust with powdered sugar.