Boil sugar, honey, glucose, and water in a pan until the thermometer reaches 160°C.
Stir in bicarbonate of soda quickly and pour onto a greased baking sheet.
Allow the honeycomb to cool completely and break it into small pieces.
Fold honey, walnuts, and two handfuls of honeycomb into the whipped cream.
Pour the mixture into a container and freeze for 15 minutes to set.
Preheat the oven to 200°C.
Caramelize sugar in a 20cm pan until golden-brown, then stir in the butter.
Cut the puff pastry into a circle slightly larger than the pan diameter.
Arrange apples in the caramel, sprinkle with thyme, and cover with the pastry circle.
Bake the tart for 20-25 minutes until the pastry is golden-brown.
Rest for one minute, then invert the tart onto a plate.
Serve the tarte tatin warm with the prepared ice cream.