Elrel, my first cookery book was a Mary Berry, an engagement present given in 1978. It, along with school cookery lessons provided by my strict Home Economics teacher, was the basis of everything I know about cooking. Mary Berry's recipes are clear and, though plain, always work. She is reliable on baking, roasting times and sauces - the tricky stuff.
These days, being retired, I have time to spice things up and I often go online to obtain recipes. In my own cooking I adapt and modify and I often write down my own recipes or those of others in a lovely book I bought for the purpose. A kind friend gave me his mother's recipe for an ordinary fruitcake and I have tweaked it until it is now just what the family loves and this too has gone in 'the book'.
I read somewhere that the over fifties are the most confident cooks. We have basic techniques on board and can adapt and rescue a disaster with the confidence we have gained. When making lemon curd for the first time I looked up many recipes and combined about three to get the taste I wanted. I used Nigel Slater's ingredients for a more sour mix and Delia's method which was quicker and easier. I have invented my own strawberry jam recipe which uses the microwave and can be done with just one punnet of strawberries. Still, I am only so-so at making bread. My DH's bread always rises better than mine. You win some and lose some!