A glum winter is brightened by citrus season: Seville oranges for marmalade, blood oranges from Sicily, bergamots (the zest of which perfume Earl Grey Tea) and leafy mandarins.

Try if you can to get hold of Japan's extraordinary citrus selection. Yuzu has become fashionable over the last decade: combined with soy sauce to make 'ponzu' or with chillies and salt to make 'koshi', another condiment.

Ham & High: Recipes for Blood Orange Salad and Bergamot tartRecipes for Blood Orange Salad and Bergamot tart (Image: Kerstin Rodgers)

I haven't travelled since I got back from Japan a year ago when I visited Shikoku, the island where they grow Yuzu. I also tried Dekopon, mandarin-like with a large orange nipple and Mikan satsumas. It's hard to describe the flavour of these, it's more a question of intensity, the most orangey-orange you have ever tasted.

Difficult to find in the UK are Meyer lemons, usually from California. Imagine a fragrant lemon with sweetness. Many exotic fruits can be ordered directly from the Natoora app, but beware; fiddling around on the iPhone, I found I'd spent a shocking £12.80 on a single yuzu once it was delivered. Both Ocado and Riverford Organic sell bergamots. This year I’ve managed to grow my own bergamot and kaffir limes from small trees.

Pomelo, like a large but less bitter grapefruit, is another citrus worth trying, especially in salads: this can be bought at corner shops in Kilburn High Road. The pith is incredibly thick. From February you can buy perfumed Bengali limes or ‘Gondhoraj Lebu’, large green knobbly citrus costing around £1.40 each from East London/Whitechapel ethnic shops.

Spend time learning to carve or 'supreme' citrus: it's the pith that is bitter and ideally you don't want the chewy membrane either. For many citrus (Bergamot, Yuzu, Bengali limes) the zest, crammed with volatile essential oils is the point, while the actual fruit can be rather dry. With limes, lemons and oranges, both zest and juice are equally valuable in recipes. I love grapefruit, increasingly sweeter varieties higher in 'Brix' (the sweetness scale) are grown, but it clashes with many medicines such as statins.

I've made this Valentine's-inspired tart with bergamot but you could also use lemon or blood oranges.

Tarte au Bergamot

Based on Pierre Hermés Tarte au citron recipe so use lemons. The heart shaped pie dish is from Homesense in Brent Cross.

Ingredients:
For the pastry
• 150 g plain flour
• 75 g unsalted butter
• 30 g almonds, ground
• 50 g icing sugar
• 1/2 tsp vanilla paste
• 1 egg yolk
• pinch salt
For the curd
• 1 bergamot zest plus juice
• 2 lemons zest plus juice
• 4 eggs
• 300 g butter, room temperature
• 240 g caster sugar
Method:
For the pastry
• Preheat the oven to 180ºC
• Rub the flour and butter together until it forms breadcrumbs
• Add almonds, icing sugar, vanilla, egg and salt.
• Knead together, cover with clingfilm and chill in the fridge for at least 30 minutes.
• Roll out the dough then press it into a greased and floured tart tin.
• Blind bake: line the pastry with a piece of parchment paper and pour in baking beans. Bake at 180ºC for 10 minutes. Remove from the oven, remove the beans and parchment paper and bake for another 10 minutes until golden. Leave to cool.
For the filling
• Combine the sugar and citrus zest in a bowl which will fit over a saucepan/bain-marie without touching the water. Stir for a few minutes.
• Add the juice and eggs. Stir constantly until the mixture reaches 82ºC or is thick and custard-like. Remove from the heat and let it cool to lukewarm.
• Pour all of it into a blender, then add the butter while the blender is running cube by cube.
• Pour the curd into the tart shell. Leave to chill then serve.
• TLDR: a shortcut is buying ready-rolled shortcrust pastry, baking as above, then adding store-bought lemon curd.

Ham & High: Blood Orange Salad is just one idea for citrus recipesBlood Orange Salad is just one idea for citrus recipes (Image: Kerstin Rodgers)

Blood Orange Salad

Ingredients:

4 blood oranges, reserve zest, remove skin and pith
1 fennel bulb, thinly sliced
4 tbsp olive oil
1 tbsp dijon mustard
Handful of chopped fresh dill

Method:

Arrange the ingredients prettily on a plate then drizzle with the dressing, fresh dill and the orange zest.

Yuzu Kosho (Japanese chilli citrus paste)

This keeps for months in the fridge. Use it to flavour rice or top noodles.

Ingredients:

1 yuzu (or substitute limes/lemons/bergamots/Meyer lemon)
1 small green chilli
1 tbsp sea salt

Zest the yuzu, taking care not to include the pith. Deseed the chilli.
In a pestle and mortar mince all the ingredients together.