In a blender, combine the sliced strawberries, fresh lemon juice, and simple syrup. Blend until smooth. Strain the mixture through a fine mesh sieve into a bowl to remove seeds and pulp.

In a cocktail shaker, combine the strawberry-lemon mixture with vodka and a handful of ice. Shake well until chilled.

If desired, rim the glasses with sugar by running a lemon wedge around the edge and dipping it into a plate of sugar.

Fill the prepared glasses with ice and pour the martini mixture over the ice.

Garnish with lemon slices and whole strawberries. Serve immediately.