- Preheat oven to 400°F (200°C).
- Line a baking sheet with foil; lightly grease.
- Cut chicken breasts in half crosswise.
- Place 1/4 cup (60 mL) milk in a medium bowl; whisk in mustard, salt and pepper.
- Place breadcrumbs and oregano in a shallow dish.
- Working with 1 piece of chicken at a time, dip in milk-mustard mixture followed by breadcrumb mixture, rolling and coating well. Set on foil-lined baking sheet.
- Bake for about 25 min, turning halfway through, until chicken is golden and cooked through.
- Meanwhile, in a skillet, melt butter over medium heat. Add garlic; cook 1 min. Sprinkle with flour; whisk to combine. Gradually whisk in remaining milk. Bring to a boil and reduce heat. Whisk for 2 to 3 min until smooth and thickened. Stir in lemon zest, feta, dill and cucumber.
- Serve chicken with sauce spooned over top.
Variation: Add about 1/4 cup (60 mL) finely grated Canadian parmesan to panko breadcrumb mixture.