Preheat oven to 425 degrees. Simmer the milk, nutmeg, 3 tablespoons of the butter, and the sea salt in a saucepan over low heat, gently whisking to combine. Once the butter melts, slowly whisk in the semolina, a bit at a time. Once all of the semolina is incorporated, switch to a wooden spoon and stir in the eggs and the Parmesan. Continue stirring until the mixture thickens. Pour the mixture onto a baking sheet lined with parchment paper. Using a spatula, spread the mixture out uniformly into a rectangle about 1-1 1/2" thick. Leave to cool completely in the refrigerator for at least 15 minutes. Once cooled, cut out round discs using a cookie cutter or a water glass. Butter a baking dish; I use a 13" x 9" rectangle non-stick dish. I find it is easier to scoop out the gnocchi in this size. Arrange the discs, slightly overlapping one another into the dish. Dot the top with the remaining 4 tablespoons of butter and a generous sprinkling of grated Parmesan cheese. Bake in the oven for 15-20 minutes, or until golden, bubbly brown.