In a kadai/pan, roast the maida for 3-4 minutes until the raw smell leaves. Set it aside.
Boil the milk in a heavy bottomed wide pan.
In the meantime, cut the muskmelon to grind it to a pulp.
In a blender, grind the cut muskmelons to a smooth pulp.
Once the milk comes to a boil, lower the heat, and let it simmer. Mix 4-5 tbsps of the milk with the previously roasted maida and stir well such that no lumps are present.
Now, add sugar to the milk on the stove.
Add the muskmelon pulp to this.
After mixing the pulp well with the milk, add the milk+maida slurry along with the vanilla essence. Stir the mixture well until it thickens. Take it off the heat, and let it cool completely.
Blend this mixture until it reaches a smooth batter like consistency. Pour it in freezer proof boxes and freeze it for 4-8 hours.
After that, blend the frozen mixture once again, and freeze it again for 8-12 hours. This repeated blending ensures that the ice cream is creamy, and not frozen like ice. The ice cream can be consumed now, or it can be beaten once again for a more creamier texture.