Thought I would try here

If what you are remembering is a sweet pastry and it is a rich one, it might be "Pâté Sucrée," and it will, indeed, have sugar, but not any overwhelming amount. There are other basic pie pastries that add a few spoons of sugar, too, but are not as sweet as Pâté Sucrée.

Most pie pastries, sweet or not, can be pressed into tart or pie pans with the hands and molded on the sides with the bottom of a measuring cup or a drinking glass. There are instructions all over online, some with videos.

Take a look around at the videos and recipes and see if any of them appeals to you.

This pastry was sort of gritty and crunchy.

Then use a shortbread recipe.

Almost certain it's a pie crust / tart base made from Graham Crackers, butter and sugar. Lots of recipes out there, just pick one with the lowest sugar. Haven't tried this Toutube one yet :-

Others' answers have sorted the recipe, but the crunchy bit sounds a LOT like the digestive biscuits I make using Donal Skehan's recipe but using FWP Mathews' _Cotswold Crunch_ flour

Crushed Digestive biscuits in the UK are known as crushed Graham Crackers in the USA

A short-cut would be to buy ready made Graham Piecrust, also available in the UK :-

I use the blunt end of a rolling pin to crush my Digestives. According to the following table, Graham Crackers may be slightly sweeter :-

cross posted to alt.bread.recipes as I believe Grahams versus Digestives has cropped up before