1. Pre-heat oven to 180C
2. Boil potatoes in salted water until tender but firm, remove to cool, in the same water add the broccoli florets and cook approximately 2 minutes. Drain well.
3. To make the sauce, melt butter in a medium pot over low heat, whisk in flour and salt, continue whisking until smooth. Slowly add the milk and continue whisking constantly until thickened and starts to boil. Remove from heat. Let cool slightly.
4. In a baking dish, starting with the diced potatoes, sprinkle of thyme, white sauce, broccoli florets cut into smaller pieces, and spread a couple more of spoonfuls of white sauce to top it off.
5. Add a sprinkle of parmesan cheese, bake for approximately 30 minutes (test for doneness after 20 minutes).
6. Let cool 5 minutes before serving. Enjoy!