Slice the chicken breast into thin strips and season evenly with 0.125 tsp sea salt, 0.125 tsp black pepper, and the dried oregano.
Heat the olive oil in a grill pan over medium-high heat and cook the chicken for 5-6 minutes, turning occasionally, until golden brown and cooked through.
Slice the halloumi cheese into half-inch thick slabs and place them on the hot grill pan for 1-2 minutes per side until charred grill marks appear and the cheese is softened.
Prepare the fresh produce by slicing the cucumber into half-moons and cutting the cherry tomatoes in half.
Spread the hummus onto a large plate or shallow bowl using the back of a spoon to create a smooth, thick base for the toppings.
Arrange the warm grilled chicken, seared halloumi, cucumbers, tomatoes, and kalamata olives beautifully over the hummus base.
Finish the platter by drizzling the lemon juice over the top and sprinkling with the remaining sea salt and black pepper before serving immediately.