Begin about 45 minutes before serving your roast beef meal. 
Preheat oven to 400 degrees F.

While the oven is heating, put about 1/4 + tsp of shortening in each cupcake pan cup.
An easier way is to use a table knife and take some shortening as you would butter for toast on the knife and scrap it on the inside of the cup.

Mix together:
    1 C milk
   1/2 tsp salt
    3/4 C flower - lightly fill the cup; don't pack flour into the measuring cup.

Don't over-mix! The mixture should be a smooth batter. The more you mix the batter, the more tough the pudding.
 
Once the mixture is mixed, place the cupcake pan in the oven and heat until the shortening is melted and heated. Don't leave it in the oven until shortening steams; this is too hot.

Remove the cupcake pan (don't let the shortening cool). Immediately pour batter into each cupcake pan cup to about 3/4 full. Start with 1/2  full to make sure you have some in each cup. If not, the empty cup will burn. Once you have some in each cup, finish distributing to even out each cup. If you have extra batter, spread it into each cup until all is used.

Return to oven and bake for about 30 minutes. This time depends on your altitude. The higher, the less time.

Your Yorkshire Pudding should look like the photo. Crisp and firm. If it isn't, the Yorkshire pudding is still delicious to eat. 

Serve and enjoy with roast beef, gravy, and veggies.