01 - In a mixing bowl, combine the softened cream cheese, mayonnaise, chopped dill, lemon juice, salt, and black pepper. Stir until fully blended and smooth.
02 - Gently fold the minced red onion into the cream cheese mixture until evenly distributed.
03 - Lay the thinly sliced cucumber on paper towels and pat dry to remove excess moisture, ensuring the sandwiches stay crisp.
04 - Spread a generous, even layer of the cream cheese mixture onto one side of each bread slice.
05 - Arrange the cucumber slices evenly across four of the prepared bread slices. Top each with a remaining bread slice, spread-side down, and press gently to adhere.
06 - Using a sharp knife, cut each sandwich into halves or quarters. Serve immediately, or cover and refrigerate for up to 2 hours before serving.