Preparation: Start by preheating your oven to 180ºC (356ºF). Take a 9-inch (23 cm) square baking tin and line it with parchment paper for easy removal of the blondies later.
Mixing Sugar and Eggs: In a medium-sized bowl, combine the sugar and eggs. Stir them together until they are well mixed.
Melting Butter: Melt the butter either in a small saucepan on the stove or in the microwave. Allow it to cool for a few minutes after melting. Once cooled, slowly pour the butter into the bowl with the eggs and sugar, mixing as you pour.
Incorporating Flour: Add the flour to your mixture, blending it in until fully incorporated. The batter will become very thick at this stage.
Adding White Chocolate Chips: Stir the white chocolate chips into the batter, ensuring they are evenly distributed.
Baking: Pour the batter into your prepared square tin. Smooth the top with a spatula or the back of a spoon. If you have sea salt, now is the time to sprinkle some over the top of the batter for an added flavour contrast, and bake in the preheated oven for about 25 minutes.
Checking for Doneness: The blondies are ready when the edges look set and the top is lightly golden and slightly crackled. A knife or toothpick inserted into the centre should come out clean or with a few moist crumbs.
Cooling and Cutting: Allow the blondies to cool completely in the pan. Once cooled, lift them out using the parchment paper and cut into 9 equal squares.