In a medium bowl stir together beer, stock, mustard, corn starch, and salt. Pour over sausage and peppers, stir to combine. Secure cover onto base. Microwave on high power 10 minutes. Remove from microwave. Let stand 10 minutes or until pressure indicator valve is in the down position.
Plate and serve
Serve with rice, pasta, potatoes, creamy polenta, or on a bun.