First, I combine the whipped cream cheese and crème fraîche in a bowl until smooth. Then I fold in fresh dill, chives, lemon zest, a tiny squeeze of lemon, salt, and pepper. Mixing thoroughly ensures every bite packs flavor, and whipping it together gives it a light, airy texture.
I slice the baguette in half lengthwise (or use demi baguette pieces) and toast it briefly—just until it’s golden and crisp on the outside. This step creates a sturdy base so the bread doesn't get soggy from the cream cheese or cucumber moisture.
I spread a generous layer of the herby cream cheese on both the top and bottom bread pieces. Next, I lay down the arugula, followed by crisp cucumber slices. I pile on the smoked salmon in a slightly overlapping fashion for a luxurious look, then top with wispy red onion and extra dill fronds if I’m feeling fancy.
I close it up, optionally wrap it in parchment or plastic, and serve immediately. Fresh is best, but if I need to prep ahead, wrapping tightly in parchment helps keep everything in place. These hold up well for 12–24 hours, though the bread softens over time.