Place all ingredients in a blender and pulse until smooth. Set aside.
Chop vegetables. Heat a frying pan over medium-low heat with the butter and oil. When sizzling, add vegetables. Stir, then cover. Cook for 5 to 6 minutes, stirring occasionally.
Remove the lid, pour in the white wine, and allow it to evaporate. At the end of cooking, add thyme, salt and black pepper. Stir, then remove the pan from the heat. Leave to cool.
Pour the whipped feta cheese into a serving dish. Garnish with the vegetable mixture, the roasted sunflower seeds, the chopped parsley, the lemon zest and the ground black pepper. Serve with croutons or rusks. Serve immediately.