In a pan over medium-low heat, add oil and shallots. Saute until softened. Add garlic and cook until fragrant and softened.
Add spinach, salt, black pepper, and lemon zest. Give it a mix. Cook, stirring frequently to wilt the spinach. Continue cooking until all the moisture has evaporated, about 8-10 minutes.
Turn the heat to low and add in canned salmon, breaking up any large clumps. Mix in the cream cheese and parmesan cheese until combined. Remove from heat.
Preheat your oven to 400F.
Roll out one sheet of puff pastry on a floured board. Place tablespoons of the cooled filling evenly across the pastry, leaving 2 inches of space between each mound.
Mix together an egg and water to make an egg wash. Brush the pastry around the filling with egg wash. Carefully add a second sheet of puff pastry on top, gently pushing the pastry down around the filling.
Using a 3 inch round cutter, cut out circles around each filling mound. Brush with egg wash and cut in a few ventilation slits on top. Optional: use a lattice cutter on excess puff pastry. Brush the pastry bites with egg wash and lay the lattice on top, gently pressing the lattice down. Use the round cutter to cut out the lattice and brush again with egg wash.
Place the pastry bites on a parchment paper lined baking sheet and bake in the oven at 400F for 15-20 minutes or until lightly golden and crispy.
To make the sauce, mix together cottage cheese, salt, dill, and lemon juice. Enjoy with salmon Wellington pastry bites!