Chess Pie

Ingredients --  Ovo-Lacto Vegeterian
A simple egg custard without bad sweeteners is Keto and diabetic-friendly.
  If you feel like skipping the crust, you could bake this in ramekins or the like, and add healthy toppings.
For recipes like this, where a "crust" is desired, I have a few ways of "cheating" to stay keto.  Many grocery stores offer pre-made pie crusts made of crushed pecan pieces.  They have a texture somewhat like graham cracker crusts, and are fairly healthy for diabetics.  It wouldn't be tough to improvise your own favorite nut crust if you have finely crushed pecans, almonds, or walnuts etc. on hand.  Mix a cup of these with about 1/2 cup softened butter and knead it out into a pie pan to make your own crust.  These can benefit from toasting in the oven for a few minutes before adding the pie filling.
Another alternative is Phyllo dough.  It's fragile and a little tough to work with but with a care and practice, even beginners can pick it up.  Phyllo dough of course comes from processed flour, but it's such a small amount of flour (a fraction of a gram per serving slice) that I don't feel guilty about using it for a crust.  Buy rolls of Phyllo dough from the refrigerated dessert section of a grocery store.  Sometimes you can find pre-made empty dessert cups of Phyllo, for making tarts, but those are relatively expensive and contain kind-of a large amount of the dough per serving.  Instead I tend to cut the sheets into sizes appropriate for my dessert -- a pie tin, or for example muffin cups or mini-loaf cups...  Then I brush warm melted butter onto a single sheet of of the cut Phyllo dough, (both sides), and layer it into the tin.  I'll pile 3 or 4 layers of the greased dough into the tin, reaching up the sides of the tin, and just naturally there will be wrinkles and air spaces which will keep your Phyllo crust light & crispy. 
Bake this dough in the tin, but without any filling, around 350 degrees for roughly 10 to 12 minutes so as to crisp it up before adding the fillings.  Sometimes there are instructions on the Phyllo package that say this.  Then add whatever filling, and bake the dessert long enough to cook the phylling ;-)  The Phyllo dough provides enough of a "crust" to taste the wheat and hold the dessert together, without adding too many carbs.

Simple egg custard pie:
Blend filling ingredients thoroughly, place in pie shell, bake at 400 deg F for 25 to 50 minutes until the custard is set with a slight jiggle when moved.  Cool to room temp then chill in fridge for 30 minutes or more.  The custard won't hold together as firmly as, say, a cheesecake -- so don't plan on eating a slice with your hands without a plate.