In a small saucepan, heat milk and butter over medium heat until butter has just melted.
In the bowl of a stand mixer fitted with the dough attachment, lightly beat egg with a fork. Add whole wheat flour, all purpose flour, salt, sugar, baking soda and yeast. Add the milk-butter mixture and mix on low until the dough comes together, about 1 minute. Mix on medium speed for an additional minute.*
Turn dough out onto a lightly floured surface and roll out to 1 inch thickness. Use a round cutter (approximately 3 3/4 inches) to cut English muffins, re-rolling the dough as needed. Place cut dough on a baking sheet dusted with semolina flour or cornmeal. Cover with a towel and allow dough to rise for 20 minutes in a warm place.*
Preheat oven to 325 degrees F. Using a nonstick skillet on medium-low heat, cook muffins for 4-5 minutes per side, until bottoms are lightly golden brown. Place muffins on a baking sheet and bake for 15 minutes.
Before serving, split and toast English muffins. Serve with butter and jam, or however you like them best.