Upon meeting the Brook Street Band, one quickly learns that there are two things more dear to their collective hearts than nearly anything else. The first, quite naturally, is the music of Georg Frideric Handel — the group takes its name from the address of the composer’s main London residence — which has been the bedrock of the Band’s work since its founding in 1996.

The second, slightly less expectedly, is food: when I caught up with the Band it was during their lunch break in the middle of a day of recording, and after tucking into one of the most sumptuous inter-session spreads I’ve ever seen, most of our conversation strands seemed to turn themselves back towards the topic of cooking, or ingredients, or picnics …

If this sounds flippant, there is a more serious side to this observation; namely, that such a lively shared interest — ‘Food is important to us!’ laughs Tatty Theo, the Band’s cellist and founding member — has helped to create a strong bond between the members of the group. This, allied to the relatively stable line-up of the Band — harpsichordist Carolyn Gibley joined in 1999, violinist Farran Scott not long after, while fellow violinist Rachel Harris was also there at the beginning with Theo but took a temporary sabbatical a few years ago — means that the group has a close-knit, yet relaxed, dynamic, which is immediately clear when watching them in action.

The quartet had retired to their usual venue of St Andrew’s church on the Raveningham estate, 15 miles south-east of Norwich — all but one of their CDs (all released by Avie Records) to date have been recorded there — to record Handel trio sonatas that are not part of collections published during the composer’s lifetime (completing, in a sense, a task begun a decade ago: the Band’s second CD was of the Op. 5 collection of trio sonatas, and they released the Op. 2 set in 2013).

As we sat outside on some of the gravestones, basking in the late summer Norfolk sunshine, Theo talks me through the background to the pieces they’re tackling. ‘It’s all music from fairly early in Handel’s career, from Italy in 1707 to his voyage to Dresden in 1719. He has such a reputation for being a great “recycler’ of music — both his own and other people’s — and if you love Handel as I do, it’s great fun to spot where the same material pops up in different places! Some of what we’re recording this time turns up in the later trio sonatas and even in an organ concerto.’

After the extended lunch break, the Band launches into a fresh piece, a sonata in B flat, the fiery semiquavers of the outer movements serving to shake off any post-prandial torpor. It’s clear that spontaneity and fresh thinking are crucial to its way of working as, after a couple of complete takes, the four musicians stop for extended discussion and dissection in which each is happy both to offer and receive detailed comments on stylistic and technical aspects. Harris remarks that the piece is clearly ‘the work of a composer writing keyboard lines for string instruments — all the string figurations are the “wrong” way round for the bow!’

They start again, changing some tempi, varying the character of repeated sections, sorting out the balance (with the help of the keen ears of sound engineer Simon Fox-Gál, who has produced all of the Band’s CDs; he’s clearly now an important part of the gang, which only adds to the openness and good nature of the sessions). From time to time the discussion between takes grows fairly animated and opinions are insistently put across, but it’s always focused, friendly, and firmly music-orientated. Finally, the infelicities are ironed out, the players loosen up, and soon they’re all smiling, even in the middle of some fiendish passages.

‘We often come together for a recording and consciously start with a clean slate, even if it’s a piece that we’ve played hundreds of times before,’ remarks Theo in the next break. ‘We’ve played together so much and for so long that we know what every gesture, every breath, every raised eyebrow means! In fact, we don’t even always rehearse a programme on the day of a performance — we’re happy to take things as they come in the concert and respond in the spur of the moment to a different phrasing here or a change in articulation there.’

The new disc will be released in 2016, to coincide with the culmination of the Band’s 20th anniversary season, an all- Handel (of course) concert at the Wigmore Hall featuring some of the group’s most popular and successful repertoire. ‘Two of our longest-standing colleagues, soprano Nicki Kennedy and bass-baritone Matthew Brook, will be joining us for the cantata Apollo e Dafne, and we’ll also be performing the ‘Oxford’ Water Music, which was the music for our first CD.’

Before then, the next big project is based around the life and career of one of Handel’s greatest vocal muses, the soprano Margherita Durastanti, for whom the composer wrote over a period of over 25 years in both Rome and London. The ‘Handel’s Italian Muse’ programme again features Nicki Kennedy, singing some of the most famous Italian cantatas, including Armida abbandonata and Crudel tiranno Amor.

Another ongoing project for the Band is a series of annual performances of Handel’s oratorios with the Holst Singers and Stephen Layton, at St John’s Smith Square; Israel in Egypt and Joshua have been done so far, and Solomon is next up, in May 2016.

‘I first came to Handel’s music through the oratorios,’ explains Theo, ‘and I’m still fond of the sacred music even though I’m an atheist. In fact, I named my two sons Solomon and Samson, after the two oratorios — and so I’m hoping to convince Stephen to programme Samson for 2017!’

The Band does occasionally stray away from Handel: they’ll be appearing in April 2016 at the venue which gave them their name with a programme entitled ‘Signor Corelli’s violin’, which also features virtuosic trio sonatas by Corelli, Handel, Leclair, Telemann and Vivaldi.

A recent expansion of the Band’s activities has come in recent years with a large-scale educational project inspired by Handel’s oratorio L’Allegro, il Pensoroso ed il Moderato. ‘Getting a Handle on Handel’ saw the group work with composer Matthew King and librettist Alasdair Middleton over three years, who drew inspiration from two very different primary school communities — in Haringey, London and in Suffolk — to create a new oratorio, supported by the PRS for Music Foundation and Arts Council England, among others.

Il Pastorale, l’Urbano e il Suburbano was premiered at Snape Maltings on 10 July this year, and involved over 150 children. At the time, Theo remarked that ‘Handel has a real genius for expressing emotion, and was a man of contrasts — lover of town and of countryside, who overcame poverty and the social limitations of his age — whose music has an almost effortless ability to transcend centuries and generations.’

I left the Band as the sun began to set in order to drive back to London, only to learn later that rather than calling it a day, they had in fact kept going into the night — not an uncommon occurrence for them, according to Theo. ‘We’ve usually relaxed about our sessions, and will curtail them or stretch them depending on how they’re going and how our energy levels are. If we’re feeling good, none of us wants to stop!’