Prepare the cucumber: Peel the cucumber and cut it in half lengthwise. Using a small spoon, carefully scrape out all the seeds. Grate the cucumber using the large holes of a box grater. Place the grated cucumber in a fine-mesh strainer, sprinkle with a pinch of salt, and let it drain for 15 minutes.

Extract cucumber moisture: After draining, place the cucumber in a clean kitchen towel and squeeze firmly to remove as much liquid as possible. This crucial step prevents soggy sandwiches later.

Prepare the green onions: Trim the root ends and any wilted green parts from the onions. Mince them very finely, keeping both white and green parts.

Mix the base: In a medium bowl, beat the softened cream cheese with a wooden spoon or electric mixer until smooth and fluffy (about 2 minutes). Scrape down the sides of the bowl to ensure no lumps remain.

Combine ingredients: Add the drained cucumber, minced green onions, chopped dill, mayonnaise, and sour cream to the cream cheese. Mix thoroughly until all ingredients are evenly incorporated.

Season to taste: Add salt and pepper gradually, tasting as you go. The spread should be well-seasoned but not salty.

Chill the spread: Cover and refrigerate for at least 30 minutes (or up to 24 hours) to allow the flavors to meld.

Prepare bread: Choose your preferred bread (typically white bread for tea sandwiches). Trim the crusts if desired.

Assemble sandwiches: Spread a generous layer of Benedictine on one slice of bread, then top with another slice. Press gently to adhere.

Cut and serve: Cut sandwiches into triangles, fingers, or squares. Garnish with dill sprigs if desired.