Slice the chicken breast into thin strips or medallions to ensure even cooking.
In a shallow bowl, whisk together the almond flour, dried oregano, garlic powder, sea salt, and black pepper.
Press each piece of chicken firmly into the almond flour mixture until evenly coated on both sides.
Heat the olive oil in a large skillet over medium-high heat until shimmering.
Place the chicken in the skillet and cook for 4-5 minutes per side until the crust is golden brown and the chicken is cooked through.
While the chicken cooks, slice the cucumber into rounds and halve the cherry tomatoes.
In a small jar or bowl, whisk together the lemon juice and Dijon mustard to create a bright, simple dressing.
Toss the mixed greens, cucumber, and tomatoes in a large bowl with the lemon-dijon dressing.
Top the salad with the warm crispy chicken and serve immediately for the best texture.