Cook pasta according to package directions. Drain well; set aside.
Meanwhile, in a large skillet, heat 1-1/2 tbsp (20 mL) of oil over medium heat. Add chicken, cook stirring occasionally until chicken is no longer pink inside and golden. Transfer to bowl and set aside.
Add remaining olive oil and sauté shallot until transparent. Add garlic and oregano and sauté a few minutes or until fragrant. Stir in tomato sauce and vodka and simmer on low heat for 5 to 10 minutes or until heated through and slightly thickened. Remove from heat.
In a small bowl, whisk Astro Original Balkan Plain 2% yogourt and cornstarch; whisk into sauce.
Add reserved chicken, spinach and basil to the skillet; return to heat and cook for 2 minutes or until spinach is lightly wilted.
Stir in pasta and cheese. Serve. Sprinkled with pepper flakes, if using.