How to scale up pudding recipe 10x?
Scaling out a recipe is often more difficult than just "multiplying" the ingredients. In the Book Ratio they have a chapter on Custard:


  The standard ratio is bedrock, 2 to 1; 16 ounces milk blended with 8
  ounces (4 large) eggs will result in 24 ounces of an excellent
  custard. Large eggs are about 2 ounces each, which makes custards easy
  to manage without a recipe: a cup of milk and 2 eggs, or ½ cup of milk
  and 1 egg. But 1 large egg will set three-quarters of a cup of milk
  into a perfect custard. So, as with all ratios, and recipes, it can
  vary. If you intend to turn the custard out and it needs to hold its
  shape, stick with the basic ratio. Extra yolks are often added for
  texture and richness. The quantity of sugar and the quantity of fat
  also affect the final outcome. If you’re using a lot of sugar, you may
  need to add a little more protein for structure. If you’re using only
  heavy cream, you may need less.
  
  Ruhlman, Michael. Ratio (Kindle Locations 3475-3481). Simon &amp;
  Schuster, Inc.. Kindle Edition.


Simply doubling a recipe is usually pretty straight forward...the more you scale upwards the more 'out of alignment' your ratios become (particularly where eggs are involved). 

Without your base recipe I have to warn 'your mileage' may vary' So be prepared to tweak it to your taste.