Bring Turkey Stock to a simmer in a medium saucepan (do not boil). Keep warm over low heat.
Melt 1 teaspoon butter and 1 teaspoon oil in a large saucepan over medium heat. Add leek to pan; cook 7 minutes or until tender, stirring occasionally. Stir in 1/4 teaspoon salt. Place leek mixture in a small bowl. Melt remaining 2 teaspoons butter and remaining 1 teaspoon oil in pan. Add shallots to pan; cook 2 minutes or until tender, stirring occasionally. Add rice; cook 2 minutes, stirring constantly. Stir in wine; cook 1 minute or until liquid is nearly absorbed, stirring constantly. Stir in 1/2 cup stock and 1/4 teaspoon salt; cook until liquid is nearly absorbed, stirring constantly. Add remaining stock, 1/2 cup at a time, stirring constantly until each portion of the stock is absorbed before adding the next (about 28 minutes total).
Stir in turkey and leek mixture; cook 1 minute or until thoroughly heated. Remove from heat; stir in remaining 1/4 teaspoon salt, pecorino Romano cheese, thyme, sage, and pepper.