Full gear for, say, three weeks in France, apart from what I would be wearing. So (if I remember it all):
spare cycling shorts
long trousers
evening shirt
two underpants
one undershirt
two pairs of warm socks
two cycling shirts (one cool and short sleeved, one warm with long sleeves)
one light sweater/warm shirt to be worn on top of the cycling shirts
a down vest
an Ikea plastic plate
a plastic tea/coffee mug, plus folding Ortlieb coffee filter
lexan cutlery
a lexan wine glass
0.7 litre of wine in a Platypus wine bag
500 grams of macaroni as emergency food,
grated cheese
a small bottle of pesto
a small flask of olive oil
a plastic jar with jam/marmelade
a tea towel
a sponge to wash the dishes
a folding piece of closed cell foam to sit on, and to use as some protection of the panniers against the sharper sides of the Trangia
toiletries
a small synthetic towel
All this in the panniers.
Strapped on the outside because like the tent they might be wet and dirty: a Goretex jacket, rain pants and overshoes
In the bar bag: phone, first aid kit, charger, medication, sun screen, spare tube and brake pads, (very) basic tools, sunglasses, leg warmers, buff, gloves
On the bike: a bottle of water, a Thermos with hot or cold water, and a 1 litre bottle of meths (the last two in a Bikebuddy).
It was a tight fit, but it worked.
Willem