Preheat the oven to 400°F (204°C).

Spread the potatoes evenly on a baking sheet.

Roast in the preheated oven for 30-35 minutes or until golden brown and fork-tender, stirring occasionally for even cooking.

Remove from the oven, garnish with fresh parsley if desired, and set aside.

Preheat the oven to 400°F. Generously season salmon with salt and refrigerate until chilled, about 15 minutes.

In a large skillet over medium heat, heat olive oil. Add onion, garlic, and a generous pinch of salt; cook until the onion is translucent.

Add spinach and stir until wilted. Stir in cream cheese, Parmesan, and dill; cook until melted and combined.

Stir in half the panko and cook until the mixture thickens; season with salt and pepper.

Rinse salmon under cold water, pat dry, and place on a sheet of puff pastry.

Spoon spinach mixture over salmon, ensuring it stays in the center. Sprinkle the remaining panko over the spinach.

Fold edges of dough over salmon, flip seam side down, and transfer to a parchment-lined baking sheet.

Brush all over with egg wash, then score the top of the dough.

Bake until the pastry is golden brown and an instant-read thermometer inserted into the salmon registers 140°F (60°C), 25 to 35 minutes.

Transfer salmon to a platter and slice.

Whisk oil, vinegar, salt, and pepper in a large bowl until combined.

Add tomatoes, fennel, parsley, and toasted pine nuts; toss to coat.

Fill glasses with ice cubes.

Pour sparkling water over the ice.

Add lemon slices to each glass.

Stir gently and garnish with more lemon slices if desired.

Serve the roasted baby potatoes, salmon en croute, and tomato fennel salad. Enjoy the meal with sparkling water.