In a large frying pan over medium-high heat, melt the butter, then stir in the mushrooms and a generous pinch of salt. Cook until golden brown. Stir in the potato starch. Add thyme, garlic and the shallot. Cook until they start to soften, 2 minutes.

Add milk, cream and cheese spread. Bring to a boil, then lower the heat to a simmer. Cook, whisking the sauce constantly, until thickened and creamy, 1–2 minutes. Remove from heat. Season with black pepper.

Spread the bread slices with butter. Place in an oven-proof skillet and toast on both sides, over medium heat until crispy and golden brown.

Spread the creamy mushrooms over toasts ( you can use 2 individual oven-proof serving dishes). Top with shredded chicken and Tartiflette cheese. Crack the eggs and broil for 4-5 minutes, depending on how you like your yolk. Season with sea salt and black pepper.

Top with chopped chives and serve immediately. Enjoy!