Place all ingredients in a food processor and blitz until blended. Alternatively zap the butter and cream cheese in the microwave until just soft but not melted. Chop up further with a knife. Add remaining tart base ingredients and stir until just combined. Shape into a ball and refrigerate covered until dough firms up.
Line a 20-25 cm quiche dish with the dough. Either roll out the dough with a rolling pin between 2 sheets of baking paper or use your fingers to press the dough into the sides and base of the dish. If the dough tears use your fingers to patch it. Create a nice line along the edges by using your fingers to shape it. Trim with a knife if need be. If dough is too soft to use, refrigerate till it firms.
Use a fork to prick the base all over. Bake at 165C/ 330 F fan forced for 10 minutes. Allow to cool while you prepare the filling.
To make the filling
Cook the bacon and onion in a frying pan until the bacon browns.
Whisk the eggs, salt and pepper, garlic and parsley in a medium bowl until smooth. Beat in the sour cream and cream and whisk till combined. Fold the cheese through the egg
Meanwhile, pour the cooked bacon and onion into the quiche base and distrubute evenly. Pour the egg mixture over the bacon and onion.
Bake at 165 C / 330 F fan forced for 40-45 minutes or the quiche has set. The centre can still very slightly jiggly and will firm up once the quiche cools.
Serve hot or cold.
Use blanched almond flour if you want a pastry more like a traditional short crust pastry. The recipe works fine with almond meal as well but it will look a bit more like a wholemeal pastry. You will find if you use almond meal that it absorbs more moisture so the base will be slightly drier.For a crustless quiche, rub the base of your quiche dish generously with butter and sprinkle with 3-4 tablespoons of either almond meal/flour or an even mix of grated Parmesan cheese and almond meal. Follow the final instructions in the recipe to cook the filling. Perfect for a simple throw together meal. You can also add the bacon and the onion without cooking if desired.If the crust starts to darken too much, cover the quiche with aluminium (aluminum) foil. This may impact on cooking times so monitor the quiche if you do this.