Preheat your oven to 375°F and slice the baguette on a sharp diagonal into twelve ¼-inch-thick pieces. Brush both sides lightly with olive oil, then arrange on a baking sheet in a single layer without overlapping for even toasting.

Toast the bread for exactly 8–10 minutes until golden-brown and crispy throughout but still tender inside—this prevents it from shattering when guests bite into it. Remove from heat and let cool for 2 minutes on the baking sheet.

While bread toasts, combine softened cream cheese, sour cream, fresh dill, Dijon mustard, lemon juice, salt, and pepper in a small bowl. Whisk until smooth and spreadable, ensuring no lumps remain and the mixture reaches almost-mousse consistency.

Spread approximately 1 teaspoon of the cream cheese mixture onto each cooled toast piece, pressing gently so it adheres without sliding off. Work quickly but deliberately—this elegant smoked salmon canapes base must cover the entire surface for moisture protection and flavor delivery.

Top each canapé with a folded piece of smoked salmon (approximately ½ oz per piece), arranging it loosely so the delicate texture remains visible. Garnish with capers, minced red onion, one thin lemon slice, and a small dill sprig placed at a slight angle for visual sophistication.

Serve immediately on a chilled platter or arrange on individual serving plates just before guests arrive. These appetizers taste best eaten within 30 minutes of assembly, though the components can be prepped separately hours ahead.