In a pint glass, gently muddle the mint, bitters and simple syrup, just enough to release the mint’s fragrant oils. Add ice and gin, shake and strain into a fresh pint glass and top with RGB.
Combine the Pimm’s and ginger beer in a Collins glass, or something similar.
Add ice until the liquid comes almost to the rim of the glass. Add the cucumber, lemon, and strawberry, plus a small squeeze of lemon juice, if you like. Use a straw to bash the fruit around a little bit. Add the mint, and serve immediately.