We start from the puff pastry. Mixing the flour and salt, then adding the room temperature softened butter and mixing them until sandy.

Add the cold water into the sandy flour and stir until it becomes a dough. Then make the dough into a square shape and cover the dough and put it in refrigerator for one hour let it take a rest.

By the time let the dough take a rest, we can’t take a rest we need to keep going 🥲. We are going to make the butter into an around 3 inches square.
To make it, we can use a baking sheet folded up into half and make a 3 inches square room. Cut the butter into small pieces and put them into the baking sheet side by side and use the rolling pin roll the butter into 3 inch square then put the butter back into the refrigerator.

One hour later, We can take the dough and butter out. Make sure the dough and the butter are in the same hardness. Spread some flour on the table and put the dough on top and knead each corner of the dough. The dough shape will be like a cross and the middle can put the whole butter in.

Put the butter in the dough and fold every corner of the dough. Make sure there is no air inside the dough.
Rolling the dough into three times longer and folding it three times then putting it back into refrigerator again for 30 minutes.

30 minutes later…Take the dough out and roll it into 3 times longer and fold it three times, and do it again then put the dough back into the refrigerator for 30 minutes until we have 3^6 (729)layers

After finishing the puff pastry part, don’t forget to put the puff pastry dough in the refrigerator. And we can start cooking the beef, spread the salt and black pepper on the beef’s surface and use the middle high heat and cook the beef for 1-2 minutes each side.

Take the beef out and spread the Dijon mustard (we can use normal mustard instead) on the beef then we put it in the refrigerator let dry and take a rest.

And we still can’t take a rest, we are going to make mushroom duxelles. Cut all the mushrooms, onion and garlic into small pieces then use middle low heat with the vegetable oil to cook them until dry, it might take 50-60 minutes and it will lose around 2/3 volume. Don’t forget to add some salt and pepper to let it have a flavor after cooking.

Now we can start combining the inside of the beef wellington. Put a plastic wrap on the table and tile the Serrano ham then spread the mushroom duxelles then put the beef on top and then roll all of them tightly then put them into refrigerator at least one hour

Take all the part out of the fridge and preheat the oven to 390-430 degrees. Rolling the puff pastry dough to 0.11-0.19 inches thick rectangle(width:11 inches length:15 inches) and put the beef without the plastic wrap on top of the puff pastry and wrap it up, and then leave the joint down.

Use knife to cut some scratches to decorate and also make the dough won’t destroy while baking.
And put it into the middle bottom layer oven and say see you 40-50 minutes later