You can make the lemon filling and put it in the puff shells. Drizzle with a little contrasting icing or other viscous fruit syrup, Or chocolate if you want to gild the lily. Or you can do a lemon curd filling with a lemon cream inc. zest.

Most home grown lemons in SoCal are Eurekas, which are pretty lemony, and can get really big, bright yellow and pleasantly acidic, or Meyers, which are half orange, very round, a bit smaller than a standard orange, and gold to orange in color. They're much sweeter than normal lemons but still taste lemony. Beyond that, as you know, there are dozens of others, but good chance it's one of those two.

I make this for special occasions: https://www.deliciousmagazine.co.uk/recipes/frozen-lemon-souffle-in-a-chocolate-shell/ 

No puff pastry but it's delicious.

Or just make lemon curd and pop it into the pastry shells.

Maybe something like this?

https://www.puffpastry.com/recipe/lemon-cheesecake-mini-tartlets/

Both Ina Garten and Lori Longbotham have recipes I use/like for lemon tarts. Easy to google if interested, although there’s no puff pastry involved.

I agree with plllog regarding your lemons likely being Eurekas and maybe Meyers. Our tree is a Eureka, and I tend to prefer their tartness to Meyers.

Linnea, just wanted to say Ina and Lori’s recipes for lemon curd are good. You’ll find Ina’s here…

https://www.foodnetwork.com/recipes/ina-garten/lemon-curd-tart-recipe-1953051

And this is Lori’s from one of her books.

I simply adore how Chloebud always has the recipes handy!

I made this last July for a Bastille Day dinner, where we had duck confit, etc based on a friend's experience at Le Pichet in Seattle ... (I couldn't find a recipe from Le Pichet but Jim Drohman the former chef has a blog site with nice recipes that I really enjoyed https://www.jimdrohman.com) .

https://www.goodlifeeats.com/lemon-cloud-tart-with-strawberry-rhubarb-compote/

I think using puff pastry as a crust would work? but I'm not much of a baker but the term 'cloud tart'' was accurate and I think about it almost weekly, it was that good!

My lemon curd recipe is quick, easy and yummy, as many here will attest 😊

Lemon Butter (Colleenoz)

4oz butter (NOT margarine)
3/4 cup lemon juice (about 3 lemons' worth)
all the rind from the lemons, grated
1 cup sugar (I use superfine)
4-5 eggs, thoroughly beaten

Put butter, sugar, lemon juice and lemon rind into a micro-safe bowl. Cook on high about 3 minutes, stirring halfway through. Butter should be melted and sugar dissolved. Beat in eggs and microwave in 30-second bursts until it thickens, about 2 minutes. Whisk after each burst. Cool and pour into sterilised jars. Cover immediately. Store in refrigerator after opening, or even before opening to prolong the shelf life, which is short.
Makes about 3 medium sized jars.

Sneaky notes:

If you are making a _lot_ of this, for gifts, etc, I peel the rind off with a peeler and drop it into the blender. Then cut off the white pith with a paring knife. Making sure there are no seeds, drop lemon flesh into blender. Whizz it up until the rind is pulverised. You should end up with about 1 cup of juice/rind mix per batch, to account for the rind and aeration. You can double or triple the recipe, just use a bigger bowl and adjust the times.
I also use the blender to whizz the eggs. If they are not totally beaten, you can get little white strings from the egg white which don't look great.
If you overcook it and it separates, beat up an extra egg. Gradually mix separated (sounds much better than curdled, doesn't it?) mixture into egg. Repeat if necessary.

Fresh raspberries go well with lemon curd.

I'd fill the puff pastry cases with a lemon custard. I think lemon curd alone is too rich.