Onion Herb Tart

Onion Herb Tart

This weeks lesson: do not buy pretty shaped tart cases that you have no experience lining.

Do not attempt to line said tart case in an angry and impatient manner. This will only result in the following: badly made pastry, pale under baked pastry case and, in the end, a broken square pastry case.

As you all know from my previous melt down, I have had trouble lining this tart case.

Ok, I wouldn’t say never buy a cool looking tart case but think about it before you do. I thought it looked pretty and didn’t really commit myself to learning how to line it. However, I’m glad I did buy it because now I know how.

I was so relieved when this onion tart was finished. It felt like a long journey, but after my first slice, I knew it had all been worth it. I ate this entire tart within 2 days whilst watching about 5 episodes of Game Of Thrones. Yeah, I’m one of those people now.

I’m still battling with my gas oven. I feel like it takes forever to bake something compared to an electric. But after talking to a girlfriend who is also having gas oven tantrums, I’m feeling better about it.

I have some really cool bread stuff coming up soon. I actually can’t wait to share it with you! I always said I wanted to start a sourdough starter, well… the time has come.

tart liningveg 3 tart 1 tart above tart filling

Ingredients – serves 8, Makes one 9 inch by 1 inch square tart

Shortcrust Pastry

  • 340g plain flour
  • 150g unsalted butter, cold and cubed
  • pinch salt
  • 3-4 tbsp. cold water


  • 40g unsalted butter
  • 2 tbsp. olive oil
  • 3 large white onions, finely sliced
  • 3 large red onions, finely sliced
  • 4 tbsp. fresh parsley, finely chopped
  • 2 spring onions, finely chopped
  • 1 egg
  • 1 egg yolk
  • 100ml single cream
  • 1 tsp. sea salt
  • 1/4 tsp. black pepper


For the pastry; place the flour, butter and salt into a medium-sized bowl. Using your fingers, begin to crumble the butter into the flouer using your thumb and index finger. After a few minutes your mixture should resemble bread crumbs. When you have reached this stage, begin to add in your water. Add in 2 tbsp. to begin with and combine using your hands. Continue to add in the rest until you reach a ball of dough that holds together well with no dry patches. You may need more or less depending on your flour. Wrap your pastry in cling film and rest in the fridge for 30 minutes.

Once rested, take your pastry out of the fridge. Flour your work surface and begin to roll out your pastry until it is about 3mm thick and a few inches bigger than your tart case. Roll the pastry over your rolling-pin and unroll over your tart case. Begin to tuck the pastry into the sides and corners of your tart tin. Once you have lined the tart tin, roll your rolling-pin over the top of the tart tin so that it cuts off any overhanging pastry. Finally, using a small knife, cut off any small pieces of extra pastry on the edges. Prick the base with a fork and freeze for 1 hour.

Pre-heat your oven to 190C fan/ 170C/gas 5. Line the inside of your frozen tart case with aluminium foil and fill with baking beans/rice. Blind bake the tart case for 10-15 minutes until the pastry is set. Remove the baking beans and foil and cook for another 5-10 minutes until light golden brown.

While your pastry is blind baking, get started on your filling.

Place the butter and olive oil in a large saucepan. Place the pan on medium-low heat. Once the butter has melted, add in the red and white onions. Cook with the lid on for approx. 20 minutes, stirring occasionally. You want your onions to be soft with no colour on them. Take the lid off and turn the heat to high. Cook the onions for 5 minutes until all the juice has gone from around the onions. Stir and watch the onions now as they can catch very easily. Take the onions off the heat and leave to cool completely.

Turn the oven down to 160C fan/ 140C/gas 3. Once the onions are cool, add in the parsley and spring onions. In another bowl, combine the egg, egg yolk, cream, salt and pepper. Pour this over the onions and stir. Pour this into your pre-baked tart case. Place in the oven for 15 minutes. Turn the oven up to 200C fan/ 180C/gas6 and bake for 5 more minutes. The tart case should be golden brown and the tart filling set.

Remove from the oven and leave to cool completely. Serve cold or warm with a vibrant side salad.

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Eva Rosenberg

Eva Rosenberg

Welcome to Eva's Kitchen where I share my adventures in cooking. My creations may not always turn out Pinterest perfect, but I usually end up with a funny picture or an interesting meal. Thanks for stopping by!


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