1) Preheat the oven to 190C/Gas 5.
2) Put butter in a 4L heavy bottom pan; melt slowly. Add the shallots and sweat for 10 minutes. Add vinegar and white wine and reduce for 15 minutes. Pour in cream and reduce by half. Transfer to blender; slowly add Cheddar while pulsing to heavy thickness. Hold warm.
3) In a medium bowl, lightly whisk 2 egg whites. In a separate medium bowl, combine all dry ingredients for the breading.
4) Place noodles, bacon, and corn in a large bowl; toss with fonduta until well coated. Place mixture in a shallow baking dish. Place a weight on top of it (e.g. another baking dish) and press for 30 minutes in the refrigerator. Once set, ring mould 5 cakes.
5) Dip top of each cake in egg white, then into breading. In a nonstick pan, melt butter and olive oil until just crackling. Place cakes, bread side down on pan. Saute 4 minutes; place in oven for 8 minutes. Remove and drain on kitchen paper. Keep warm.
6) For the puree, melt 110g of the butter. Saute shallots 5 minutes. Add celery root and milk and cook over medium heat for 20 minutes. Drain and place celery root in a blender. Add the remaining 110g of butter and blend until smooth adding the cream, as needed. Season truffles with salt, pepper, and white truffle oil. Stir in truffles. Keep warm.
7) To serve, place a pool of celery sauce on each plate. Place macaroni and cheese cake in center. Garnish with baby celery and chive oil.