Drain the defrosted spinach well until there is no excess water.
In a large bowl, combine the drained spinach, mayonnaise, sour cream, vegetable dip, and water chestnuts.
Add the bacon, reserving about 1/4 cup for bacon for garnishing the top of the bread bowl.
Mix ingredients together well, being sure that everything is combined.
Cover and refrigerate dip for 2-3 hours before serving.
If you'd like to serve the spinach dip in a bread bowl, take a large round loaf of sourdough bread and hollow out the center. Be sure to clear at least one or two cups of bread from the inside, while ensuring there's enough bread to create a wall. Add spinach dip into the hollow bowl and garnish with additional bacon before serving.
Notes
The calories shown are based on the recipe being divided 15 ways, about 1/3 cup per serving, not including bread. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate.