Peach Cake Filling

WARNING: Under normal circumstances, I try to share only recipes which I have tried time and again under varying circumstances, and which I know are winners for the crowd I cook for. That is not the case with this recipe. I have cooked it exactly once, and that time was on Mother's Day. I am posting it because Mrs. Weathercolour asked me to share it with her, and I felt that a) blogging it was an efficient means of getting it to her, and b) if anyone else wants to try it and give me feedback (it is so rich that we won't be doing it too often around here, so it may take a long time to perfect) I would be very pleased.

1 29-oz can sliced peaches in syrup
about* 1/4 cup corn starch
1/2 c. vanilla sugar
1/4 t. salt
1/2 t. almond extract (yes, this is almost the limit of how much it can take)
2 T butter

Dump the peaches into a saucepan. Combine the sugar and the salt with the cornstarch, and mix it well enough that the cornstarch won't be lumpy after you add it to the peaches. Then add the sugar mixture to the peaches. Cook all this, stirring "constantly" (meaning, just like lemon meringue pie filling and white sauce, you can get away with neglecting it for small periods of time, especially if you have a wire whisk on time) until it comes to a boil; let it boil for 1 minute; then take it off the heat. Add the butter and the almond extract, and stir them in. Mine ended up a little soupy, but then I'm not sure I added a full quarter cup of cornstarch. But I'm not completely sure I didn't. *sigh*

The cake I put this on/in was a regular box-mix yellow cake. Nothing too exciting. I baked it in two 8-inch rounds, and put the filling in between the layers, on top, and then spooned a little more on to each slice. I knew I had gotten the balance of flavors just right when it became difficult to stop snitching it. If only I could be sure that I've recreated that mix in the proportions of this recipe. Do please let me know.

*The truth about the measurements is that ALL of them are approximate (even the size of the can of peaches-- I compared to a can upstairs, but I used one from downstairs, which might have been an ounce or so different?), but the cornstarch measurement is particularly approximate.