Thinly slice the mushrooms. Strip the thyme leaves from the stems. In a medium [large] frying pan over medium-high heat, warm 2 to 3 teaspoons oil until hot but not smoking. Add the mushrooms, season generously with salt and pepper, and cook, stirring occasionally, until the mushrooms are lightly br

Cut a small corner from the burger packaging and drain off any excess liquid. Transfer to a plate; pat dry with a paper towel. Season with salt and pepper. In a large frying pan over medium-high heat, warm 2 to 3 teaspoons oil until hot but not smoking. Add the patties and cook until starting to bro

Remove the green hulls from the strawberries; thinly slice the berries. Trim the root ends and any coarse stems from the watercress; coarsely chop the watercress. Strip the basil leaves from the stems; coarsely tear the leaves. In a large bowl, toss the strawberries, watercress, and basil with the M

In the same pan used for the patties, place the buns, cut sides down, and cook over medium-high heat until lightly toasted, 1 to 2 minutes. Place the bun bottoms, cut sides up, on a work surface. Top each with a burger and mushrooms. Close with the bun tops.

Transfer the burgers and the strawberry and watercress salad to individual plates and serve.