This is from my mother's Betty Crocker Recipe Card Library from the 70's. I've been enjoying it for 3 decades! It's so delicious, and not as hard as the recipe is lengthy. It makes even a novice cook look pretty darn impressive!
05(I just do this on a floured surface.) Roll out into a rectangle.
06Spread with filling.
07Roll up to make a long roll.
08Place sealed edge down on greased baking sheet.
09(I make a circle or a half-circle.) With scissors, make cuts 2/3 deep at 1"-2" intervals.
10(I slightly turn each piece to show filling.) Brush top with reserved egg.
11Bake at 375F for 25-30 minutes.
12Meanwhile, make cheese sauce.
13Cheese Sauce: Melt butter over low heat.
14Blend in baking mix, salt, and pepper.
15Cook over low heat, stirring, until smooth and bubbly.
16Remove from heat.
17Stir in milk.
18Heat to boiling, stirring constantly.
19Boil and stir one minute.
20Stir in cheese until melted.
21(I rarely bring this to a boil. I just make sure it's nice and hot, bringing the heat up slowly. Maybe it's my own quirk, but I don't scorch the milk that way. I slice the tuna ring and serve the slices and pass the cheese sauce. This is so yummy!).