Cook orzo in salted boiling water according to package directions until just barely al dente, about 7 to 8 minutes. Drain and set aside.

Pat chicken breasts dry with paper towels, then season generously with onion powder, garlic powder, paprika, salt, and pepper. Heat 2 tablespoons olive oil in a skillet over medium-high heat and cook chicken for 6 to 7 minutes per side until golden and internal temperature reaches 165°F. Rest for 5 minutes, then dice into bite-sized pieces.

In a large skillet or Dutch oven, melt butter with remaining olive oil over medium-high heat. Add diced onion, carrots, and celery. Sauté for 4 to 5 minutes, stirring occasionally, until vegetables soften and onion becomes translucent.

Reduce heat to low and sprinkle flour evenly over the softened vegetables. Stir constantly for 2 to 3 minutes to cook out raw flour taste and create a golden roux.

With heat still on low, slowly whisk in chicken broth followed by heavy whipping cream. Keep whisking continuously until you have a smooth, lump-free sauce that begins to thicken, about 3 to 4 minutes.

Sprinkle in chicken bouillon powder and stir in diced chicken. Let mixture simmer gently for 3 to 4 minutes until sauce reaches desired consistency. Fold in cooked orzo and stir until creamy and well-combined. Heat through for 2 minutes, then serve immediately.