Step 1

Spray 5- to 6-quart slow cooker with cooking spray.

Step 2

In 12-inch nonstick skillet, heat 2 tablespoons of the oil over medium-high heat. Add shallots; cook 3 to 4 minutes, stirring frequently, until starting to brown. Add mushrooms; continue cooking 3 to 4 minutes, stirring frequently, until tender. Stir in garlic; cook 30 to 60 seconds or until fragrant. Remove from skillet to small bowl.

Step 3

Rub brisket with remaining 1 tablespoon oil; season with salt and pepper. Heat skillet over medium-high heat; add brisket, and cook 1 to 2 minutes on each side, until browned. Place fat-side up in slow cooker; top with shallot mixture.

Step 4

In small bowl, mix 1/2 cup broth, the Worcestershire sauce and soy sauce. Pour into slow cooker around beef brisket. Cover; cook on Low heat setting 8 to 9 hours or until brisket is very tender. Transfer beef to cutting board; cover and keep warm. With slotted spoon, transfer shallot mixture to small bowl.

Step 5

Strain cooking juices using fine mesh sieve, and reserve 1 1/2 cups of the strained juices; transfer to 1 1/2-quart saucepan. In small bowl, mix remaining 2 tablespoons beef broth and the cornstarch with whisk; beat into cooking juices in pan. Heat to simmering over medium heat 2 to 3 minutes, stirring constantly, until slightly thickened. Remove from heat; stir in whipping cream.

Step 6

Cut beef into 1/2-inch slices, cutting against the grain. Transfer sliced beef to serving platter, using large flat spatula or fish turner. Top beef with shallot mixture; drizzle with sauce before serving. Garnish with chopped parsley. Serve with mashed potatoes.