The Cowboys held the Saints to 10 points last season - when New Orleans had Drew Brees at QB. Teddy Bridgewater is a massive downgrade. Dallas is giving up fewer than 15 points per game this season. Bridgewater is not a downfield threat and doesn't have the mobility he once possessed. The Cowboys have the athletic and quick linebackers needed to contain Alvin Kamara and Bridgewater's short passing game. 
Dallas is well balanced and the healthier team. Dak Prescott is playing the best of his NFL career. The Cowboys rank fourth in scoring averaging 32.3 points. If the Saints load the box to stop Ezekiel Elliott, Prescott can beat them through the air. Dallas is much more dangerous offensively with new offensive coordinator Kellen Moore calling the shots.
The Saints are overrated at home where they have failed to cover in their past five games at the Superdome. They also are just 1-7 ATS in their last eight overall games.
Dallas is the superior team right now on both sides of the ball. It shouldn't be too much to ask the Cowboys to beat the Brees-less Saints.