Saw this one in Taste of Home's Feb-Mar 08 issue; made a few adjustments to suit our tastebuds, and this is the lovely result! This will put a smile on your face as the aroma wafts through the kitchen!
Fry bacon, drain, crumble; remove from pan, pour off grease; set aside.
Separate crescent rolls into triangles, place in ungreased 9-inch pie plate (points toward the center), press seams together over the bottom and up the sides to form the crust; spread with mustard; set aside.
Preheat oven to 375.
In bacon pan, melt butter; saute asparagus, onions & mushrooms until tender-crisp.
In a large bowl, combine custard ingredients; NOTE: if you didn't beat eggs first -- do that before adding the other custard ingredients -- stir in veggies, bacon, and cheese; pour into prepared crust.
Bake for 25-30 minutes (knife comes out clean); let stand 5 minutes before cutting.