Brown all sides of beef Shank Cross-Cut in 6-quart pressure cooker using sauté or browning setting, as desired. Add 1/2 cup stock to pressure cooker. Close and lock pressure cooker lid. Use beef, stew or high-pressure setting on pressure cooker; program 40 minutes on pressure cooker timer.
Meanwhile, heat oil in large heavy-bottom stock pot over medium-high heat until pot is almost smoking. Slowly whisk in flour until combined. Cook 2 to 3 minutes, whisking continuously until it turns a milk chocolate color. Reduce heat to medium; slowly add onions as oil mixture may splatter. Cook 1 to 2 minutes until oil mixture turns dark chocolate color. Add celery, bell pepper, garlic and thyme; cook 4 to 6 until vegetables are soft. Add hot sauce, Worcestershire and tomato paste; cook 1 to 2 minutes. Whisk in remaining quart of stock; bring to a boil. Reduce heat to medium, add sausage and Creole Seasoning; simmer 30 minutes.
Use quick-release feature to release pressure; carefully remove lid. Remove beef from pressure cooker; discard cooking liquid. Shred beef into bite-sized pieces. Add beef to vegetable mixture; stir to combine. Serve Gumbo with rice, onion, okra and jalapeños, as desired.
Nutrition information per serving: 596 Calories; 342 kcal Calories from fat; 38 g Total Fat; 9.5 g Saturated Fat; 0.5 g Trans Fat; 5.5 g Polyunsaturated Fat; 14.4 g Monounsaturated Fat; 101 mg Cholesterol; 1751 mg Sodium; 19 g Total Carbohydrate; 1.3 g Dietary Fiber; 41 g Protein; 6.2 mg Iron; 921 mg Potassium; 7.5 mg Niacin; 0.5 mg Vitamin B6; 3.2 mcg Vitamin B12; 9.4 mg Zinc; 31.9 mcg Selenium; 14.9 mg Choline;