Heat 2 tablespoons olive oil in a large skillet over medium-high heat until shimmering.

Add the sliced chicken in a single layer. Cook without moving for 1 to 2 minutes until browned, then stir and continue cooking until no longer pink, about 4 to 5 minutes total.

Push the chicken to one side, add the minced garlic, and cook for 20 to 30 seconds until fragrant.

Add the mixed vegetables, oregano, paprika, salt, and pepper. Toss everything together.

Stir-fry for 5 to 7 minutes, stirring often, until the vegetables are tender-crisp and the chicken is cooked through.

Squeeze the lemon juice over the skillet and toss to combine. Taste and adjust seasoning.

Remove from heat and sprinkle with fresh parsley before serving.