In a small bowl, mix together yeast, sugar, and warm water. Set aside until foamy, about 5 minutes.
In a large bowl or bowl of a stand mixer, combine yeast mixture, milk, butter, 2 cups flour, cinnamon, salt, and raisins. Mix well, adding the rest of the flour in small increments until a cohesive dough forms.
Place dough on a surface lightly dusted with flour. Knead for about 6 minutes, adding more flour as necessary to prevent sticking. Place dough ball in a greased bowl, cover, and let rise in a warm place until doubled in bulk, about 1 hour to 90 minutes.
When dough has risen, dust a baking sheet with cornmeal.
Pour risen dough out onto a flour-dusted surface and pat into a 1/2-inch thick oval. Using a large circle cutter, cut out dough rounds and place onto prepared baking sheet. Repeat with remaining dough until all is used, re-forming as necessary. Cover baking sheet with a kitchen towel and let rise until puffy, about 10 minutes.
Heat a heavy skillet over medium-low and add a small amount of butter to grease the pan.
Place four pieces of dough on the skillet and cook for 8 minutes per side. Remove to a rack to cool completely and cook remaining dough.
Split English muffins with a fork, toast, and serve with butter or your favorite jam.