In a medium bowl, whisk together the warm milk, yeast, sugar, and warm water. Let it sit until it looks foamy, about 5-10 minutes. If it doesn't foam, start over or the crumpets will be dense.

In a large mixing bowl, sift the flour, salt and baking soda together.

Stir in the yeast mixture until combined.

Put the mixing bowl in a warm spot and let it sit for 45 minutes. After the resting time, the mixture will have increased and should look very bubbly and active.

Place a non stick skillet over a low heat.

Grease the inside of the crumpet rings with vegetable oil and put them inside the skillet.

Pour a level 1/4 cup of crumpet batter into each crumpet ring. The rings should be about two-thirds full.

Cook for 4-5 minutes after which time you will notice bubbles appearing on the surface. These bubbles are what make the characteristic holes on the crumpets. If you overfill the crumpet rings or cook them on a heat that is too high you will not get as many holes.

When the surface of the crumpets are covered with holes and you can see the sides of the crumpets are golden brown, carefully slide the crumpet rings off. The rings will be hot so be careful.

You can flip the crumpets over but you may lose some of the holes where the batter on top is still a little wet. For perfect crumpets finish them by cooking them under a hot broiler for a few seconds.

Serve immediately while still warm or store the crumpets in an airtight container and toast to reheat later.