Note: Lemons vary in size and juiciness, so you will probably need between 8-11 large lemons. I ended up using 8 large lemons and 2 large english cucumbers.

Squeeze lemons until you have 2 cups of juice. Set the lemon juice aside for now.

Peel and chop the cucumbers, then use a blender to liquify them.

Strain the cucumber purée through a sieve into the pitcher.

You can use a spoon to swirl the cucumber purée around, pressing more through the sieve. Discard any solids. You need 2 cups of cucumber juice.

Strain the lemon juice through the sieve into the pitcher to remove any seeds, then stir in the cold water.

Next, add in the liquid stevia a tiny bit at a time. Stir and taste test between each addition. Stevia is incredibly sweet and a little bit goes a long way.  I used about 1 1/2 teaspoons of stevia. You may need more or less depending on how sweet you like your lemonade. You can also add more cold water now to dilute the lemonade if you prefer.

Keep refrigerated until ready to serve. Serve in glasses filled with frozen melon balls or ice cubes.